1. Introduction

In an increasingly interconnected world, contemporary diplomatic challenges require effective mechanisms and methods to address complex global issues. The two methods that can be valued and effective today are multilateral and bilateral methods. The multilateral approach involves the participation of multiple countries or actors through international organizations. This is the process of coordinating national policy among coalitions of three or more nations using ad hoc structures or mechanisms [1]. Multilateralism enables countries to concentrate resources, allowing them to share the burden of complex and expensive actions. Collaborating with other countries can also make actions more legitimate domestically and internationally, thereby gaining more support. In contrast to multilateralism, Geoffrey Wiseman [2] first used the word polylateral diplomacy in 1999 and described it as the act of a partnership between an official entity and at least one unofficial, non-state body. Polylateral methods involve smaller groups of countries or participants gathered together based on common interests or specific problem areas. Compared to the two, multilateralism emphasizes inclusivity, consensus building, and adherence to international norms and rules. Polylateralism can lead to more targeted discussions and faster decision-making. However, there has always been controversy over which of these two methods is more effective for today's diplomatic challenges. This article will argue that demonstrating multilateral approaches to addressing contemporary diplomatic challenges through climate change, global epidemic, and terrorism would be more effective than polylateral approaches.

2. Climate Change

Since the 19th century, climate change has been a concern for both developed and developing countries [3]. Therefore, the struggle against climate change is a challenge for all of humanity, not just for modern diplomacy. Everyone must take part in reducing the effects of climate change, starting with each individual citizen, then on to each government, and finally each nation. First of all, international policies have a higher chance of being successful in reaching significant social, economic, and environmental sustainability goals. Second, multilateral accords are consistent with norms of fairness and reciprocity, and if other nations are putting more effort into their national policies to meet the objective of reducing global warming, these standards will enhance their readiness to shoulder the cost of climate action. For instance, the Central Cooperation Framework of the United Nations Framework Convention on Climate Change, which involves more than three nations and is focused on solving global climate change, is a multilateral agreement. As a foundation for global collaboration to address climate change, the Convention was ratified by a number of nations in 1992 [4]. All nations have been exhorted to work together for the common good of humanity and the planet as we know it by the UNFCCC, which has played a leading role.

The UNFCCC has established some of the most significant multilateral environmental agreements (MEAs) in modern history in spite of some enduring disagreements that cut across all the themes and subjects that were up for negotiation [5]. This covers both the Paris Agreement and the Kyoto Protocol. The importance of these multilateral environmental accords rests in the fact that they are put into practice within the framework of the internationally accepted principles and procedural rules that UNFCCC must provide to guarantee inclusive involvement of all nations in the international community. The United Nations Framework Convention on Climate Change has also succeeded in passing arduous negotiations that directly affect the legal framework of these international agreements. It is thought that multilateral strategies continuously encourage the global adoption of workable national climate change response measures. Through this accomplishment, UNFCCC shows that global climate change governance is still an important and crucial component of all nations' present and future efforts at sustainable development.

However, in the face of the differences between scientific and international policy responses, some people have concluded that multilateral processes are too slow and ineffective, and should be replaced by targeted arrangements between a few countries. Using polylateral methods instead of multilateral methods. Climate change is a worldwide issue, according to Christina Figueres [6], Executive Secretary of the United Nations Framework Convention on Climate Change, mentioned in a lecture that climate change is a global issue. No country will not be adversely affected in any way. Emissions do not respect national borders, and what happens to a country's greenhouse gas emissions will not only stay in that country. The multilateral approach allows each country to contribute to the solution in some way. Whether through reducing self-emissions, developing, or installing clean technologies. Although multiple countries and even global participation make negotiations more complex, it also makes the ultimate solution - low-carbon living becomes possible and more cost-effective. The multilateral approach can serve as a global accounting system to monitor progress, under which all countries follow the same measurement and reporting rules.

All in all, an international public concern is combating climate change. The atmospheric resources of the planet are considered public assets, and global governance and effects of climate change are both present. It is challenging to respond to climate change successfully if a single nation relies solely on its own efforts. So multilateral approaches are more useful and effective than polylateral approaches. The international cooperation promoted by multilateral methods is the goal and path of global climate change planning.

3. Global Epidemic

Global health has entered a crisis as a result of COVID-19. Until today, the crisis brought about by this global epidemic has not yet been resolved. According to the United Nations Conference on Trade and Development's (UNCTAD) assessment, the impact of COVID-19 on the tourism industry alone might result in worldwide economic losses of nearly $4 trillion [7]. Moreover, This catastrophe is even more terrible for the relatives of the deceased because tens of millions of people have also fallen into deep poverty as a result. Every nation's health sector is now weak due to the overburden on its healthcare services. More importantly, with the development of the epidemic, nationalism has begun to rise. Multilateralism has been eroded in many fields, damaging many communities, especially in developing countries. In fact, epidemics represent the main international diplomatic challenges of today's era. And pandemics like COVID-19 will only become more, and possibly even worse, previews of pandemics. Global health threats may appear more frequently, spread faster and take more lives.

Globalization ensures that the vulnerability of any country can trigger crises on a global scale, as confirmed by COVID-19. Additionally, pandemics have shown their universal characteristics in affecting all aspects of global life. Looking at its indelible mark, as far as the global health crisis is concerned, the pandemic problem seems insurmountable. Therefore, the ongoing pandemic is exacerbating this global health disaster, necessitating a global response. Through the use of global health diplomacy (GHD), it must be converted from a unilateral response to a multilateral strategy with a long-term and comprehensive outlook. Kickbusch [8] stated that the policy environment for global health and non-health sectors is guided and controlled by GHD. This is a multi-party negotiation process. GHD uses legally binding or non-binding agreements supported by global governance organizations, which is an interdisciplinary concept that links the health sector with international relations and meets global health and safety needs [9]. Nevertheless, to successfully avoid the next pandemic, strengthening multilateralism is necessary. Multilateralism and significant public-private investment projects, not merely government cooperation, are the only ways the globe can create the essential supply ecology. Consequently, it is essential in addition to collaborating with important financial institutions like the World Bank, the International Monetary Fund, and regional development banks. In order to create future resilience, it is also vital to use a polylateral strategy and create inclusive multi-stakeholder partnerships, which include members of the commercial sector, civil society, and international organisations [10]. However, it should be noted that multilateral approaches are still the main approach. Overall, despite the ban on international travel, the fact that diseases are still increasing once again proves that globalization is a fact. This is due to the degree of interweaving of the entire global value chain. In order to build a rule-based world order in a globalized society, this interdependent global value chain requires multilateralism.

4. Terrorism

Nowadays, under the influence of globalization, the security situation of countries has not improved, and the threats to national security are more diverse than before. It is no exaggeration to say that the government cannot unilaterally provide national security. In many cases, only through collective security and multilateral cooperation systems can threats be eliminated to maintain national security. The issue of terrorism is one of the most fundamental threats faced by all countries. Currently, influenced by globalization and communication and information technology, the phenomenon of terrorism is becoming increasingly widespread and powerful. Compared to the past, it has many destructive effects and almost no country can escape its danger

No nation can successfully fight terrorism on its own. It calls for intensive coordination and tight collaboration. The multilateral setting can offer the best arena for the advancement of counterterrorism-related concerns. For instance, the Organisation of American States hosted the 17th regular meeting of the Inter-American Committee against Terrorism (CICTE) in April 2017. OAS/CICTE was established in 1999 [11]. It is not only aimed at promoting and encouraging member states to cooperate in preventing, combating, and eliminating terrorism. It also aims to prevent the financing of terrorist activities, strengthen cybersecurity efforts, and strengthen border control and law enforcement throughout the hemisphere [12]. CICTE works closely with its member states to develop policies and implement plans to address these issues, and is seen as a model for other regional organizations committed to combating the threat of terrorism. Delegations from 28 member states participated in this regular conference to talk about the twin issues of terrorism financing and the spread of weapons of mass destruction. It is worth mentioning that the US government is a staunch supporter of CICTE, providing personnel and assistance since its establishment. Since 9/11, the United States has taken the lead in the international community's initiatives to combat terrorism. The United States has always taken a multilateral approach to overthrow the Taliban government in Afghanistan and eliminate the Al Qaeda network there as a source of terrorism [13].

Furthermore, another illustration of a multilateral strategy for solving international counterterrorism concerns is the Global Counterterrorism Forum (GCTF) [14] . Governmental organization GCTF was founded in 2011. The European Union and 29 other countries make up its membership. The Global Counter Terrorism conference (GCTF) is a policy conference that brings together professionals from various fields to discuss strategies to counter violent extremism and terrorism. The GCTF is composed of diverse members, including traditional and non-traditional participants. For example, governments, international organizations, and civil society groups. It comprehensively demonstrates the inclusiveness and integrity of multilateral approaches, allowing for a comprehensive and collaborative counter-terrorism approach, ensuring the participation of major stakeholders, and cultivating a sense of shared responsibility. In summary, many countries have responded through multilateral coordination, pooling resources, and establishing forums to formulate international norms to effectively combat terrorist attacks. By promoting cooperation among countries, it not only enhances the ability to combat terrorism in a comprehensive and sustainable manner, but also recognizes that no country can effectively address this complex global challenge alone. This is also why the polylateral approaches cannot be used because it lacks involvement with smaller countries or stakeholder groups, which may result in the exclusion of key participants and viewpoints.

5. Challenges and Limitations

Overall, while multilateralism fosters global cooperation and inclusivity, it often encounters significant bureaucratic hurdles. The process of reaching consensus among numerous countries may be slow and cumbersome, leading to delays in responding to urgent issues. Political constraints are also common, as decisions within multilateral institutions are constrained by the different interests and policies of member countries. This can sometimes lead to agreements being diluted, lacking necessary strength or targeting, making it difficult to be effective. Additionally, since multilateral agreements often rely on voluntary compliance by sovereign countries and lack strict enforcement mechanisms, enforcement and compliance issues have always been a challenge.

On the other hand, polylateralism, while offering greater flexibility and speed in decision-making, faces its own set of challenges. The participation of non-state actors, although beneficial in many ways, also brings questions of accountability and legitimacy. These actors may not always be subject to the same guidelines and regulations governing state actors, leading to concerns about the consistency and fairness of their participation. In addition, Furthermore, polylateral initiatives may lack the comprehensive scope and resources that traditional multilateral institutions bring, potentially limiting their impact on large-scale global issues. The reliance on a selected group of participants also raises concerns about representativeness and inclusivity, which are crucial for addressing global challenges that affect diverse populations.

6. Conclusion

In conclusion, as discussed in this article, many contemporary diplomatic challenges such as climate change, global pandemics, or terrorism are essentially global issues. Therefore, compared to multilateral approaches, multilateral approaches appear more effective due to their comprehensive understanding and the participation of numerous countries and organizations. The advantage of multilateralism lies in its ability to mobilize a wide range of resources, expertise, and capacity building, which is crucial for addressing complex and interrelated global challenges. Although polylateral approaches have flexibility, their limited scope of participation may lead to limitations in financial resources, intelligence sharing mechanisms, and joint capacity building initiatives, making it difficult to fully address these issues.

Looking towards the future, the diplomatic landscape may be influenced by several key factors. The increasing influence of digital technology and social media is expected to change the way diplomatic communication and participation are conducted, making them more direct and convenient. This technological transformation may promote greater participation of non-state actors and the public, thereby strengthening polylateral diplomacy. However, it also poses challenges in terms of information authenticity and diplomatic security.

Moreover, transnational issues such as climate change and global health crises are becoming increasingly prominent, and international cooperation needs to be strengthened. In this case, the role of multilateral institutions may evolve to accommodate more flexible polylateral elements, forming a hybrid diplomatic form that combines the advantages of both methods. This hybrid model can respond more flexibly to global challenges while maintaining the legitimacy and comprehensive framework of multilateralism.

In essence, the geopolitical landscape is constantly evolving, and emerging powers are exerting influence on the international stage. This transformation may lead to a reassessment of traditional diplomatic models, as well as the emergence of new alliances and partnerships, further shaping the dynamics of multilateral and polylateral diplomacy.

Thus, multilateral approaches are more inclusive and in line with international norms. Currently, they are more suitable for promoting stability and ensuring global cooperation. However, the constantly changing global situation requires a dynamic and adaptable approach. The future of diplomacy may lie in the ability to integrate the inclusivity of multilateralism with the agility of polylateralism, crafting a more resilient and effective response to the complex diplomatic challenges of the 21st century.