The  post-World  War  II  international  legal  order  has  been  built  on  the  foundations of multilateralism,   cooperation,   and   the  rule  of   law.   International   trade   and   investment, environmental  protection,  criminal  accountability, and  cross-border  governance  have  all  been developed through treaties, customary norms, and international institutions designed to regulate state conduct and advance common global interests. However, in recent years, this multilateral consensus has come under increasing strain due to a growing wave of state unilateralism—a trend in which states act independently of, or even contrary to, established international legal norms and institutional mechanisms.

Unilateralism  in international  economic  law has  become  particularly  visible.  A  notable example is the imposition of broad trade tariffs under the so-called “Liberation Day” policy by the United States in April 2025. This policy introduced sweeping import tariffs justified based on national economic security, prompting retaliatory measures and WTO complaints. While such acts are often framed as protecting national interests, they challenge the credibility and effectiveness of multilateral institutions like the World Trade Organization (WTO) and question the stability of international trade and investment regimes.

Beyond trade, unilateral action is increasingly shaping other branches of international law. Some states have unilaterally withdrawn from Bilateral Investment Treaties (BITs) or terminated Investor-State Dispute Settlement (ISDS) mechanisms in international investment law, citing concerns over regulatory autonomy and public interest protections. This trend has raised legal uncertainties and increased fragmentation in the investment landscape. In international climate change law, state unilateralism is reflected in instances such as the withdrawal from global environmental accords, including the United States’ past withdrawal from the Paris Agreement, or countries pursuing energy policies at odds with global emission reduction commitments. These actions erode collective environmental responsibility and hinder the enforceability of climate obligations. In international criminal law, certain powerful states have rejected or failed to cooperate with international tribunals, such as the International Criminal Court (ICC). Non-ratification, refusal

to extradite suspects, and shielding of nationals from prosecution are unilateral decisions that compromise the global project of accountability for mass atrocities. In border securitisation and migration,  states have increasingly  relied  on  unilateral  and  extraterritorial  measures—such as pushbacks at sea, border walls, or third-country processing of asylum seekers—raising complex legal and ethical issues under international refugee and human rights law.

These varied manifestations of unilateralism pose serious challenges to international law’s coherence, legitimacy, and enforceability. They also reflect deeper tensions between the assertion of state sovereignty and the demand for international cooperation in addressing complex transnational issues.

This international conference is convened to critically assess the resurgence of unilateralism in the development and enforcement of international law. It examines how unilateral state practices reshape legal norms across different domains—particularly trade, investment, climate, criminal accountability, and border governance. The conference will also explore the implications of these developments for the legitimacy of international institutions, the evolution of global legal frameworks, and the prospects for renewed multilateralism in an increasingly fragmented world order.

1. To critically examine the rise of state unilateralism in various branches of international law, including trade, investment, international criminal law, climate change law, and border governance.
2. To analyse the legal implications of unilateral actions by states on the stability, coherence, and legitimacy of multilateral legal frameworks and international institutions.
3. To  explore  case  studies  and  recent  developments—such  as  unilateral  tariff  regimes, withdrawal from treaties, non-cooperation with international tribunals, and extraterritorial border control  practices—as  a  basis  for understanding  contemporary  challenges to  the international legal order.
4. To assess the compatibility of unilateral state practices with international legal principles, including sovereignty, pacta sunt servanda, non-refoulement, and common but differentiated responsibilities.
5. To identify  the consequences of unilateralism for developing and less powerful states, especially in areas where the retreat from multilateralism exacerbates legal asymmetries and power imbalances.
6. To propose pathways for strengthening multilateral legal responses to unilateral behaviour, including potential legal reforms, institutional innovations, and accountability and dispute resolution mechanisms.
7. To promote cross-disciplinary and comparative perspectives on the drivers, patterns, and impacts of unilateralism in international law, fostering deeper understanding across legal subfields and regional contexts.
8. To  facilitate  dialogue  among  academics,  policymakers,  practitioners,  and  civil  society actors regarding  the  future  of  international  law  in  an  era  of  growing  nationalist  and protectionist agendas.

The International Conference is hosted by the Department of International Law at the Faculty of Law, Universitas Islam Indonesia, in collaboration with the Indonesian Society of International Law Lecturers (ISILL) Association. The International Conference is intended to be and administered as an academic forum for all members of academia in law and legal studies around the globe. Thus, students, lecturers, professional researchers and the likes are welcome to participate.

1. Day, Date                :       1th – 4th of August 2025
2. Time                         :       30 Western Indonesian Time (Jakarta Time) – end
3. Venue                      :       Auditorium  on  the  4th   Floor,  Faculty  of  Law  Building, Universitas Islam Indonesia, Kaliurang Street KM. 14.5, Sleman Regency, Special Region Yogyakarta, Indonesia.

1. The Plenary Session at the International Conference will be delivered by the Speakers with varied topics related to the grand theme of the International Conference.
2. Panel Presentation of the Selected Participants that will be divided into Chambers.
3. ISILL Meeting
4. Excursion

Abstract submission                                  :    1st – 14th of July 2025

Paper Acceptance Notification (LoA)     :    18th of July 2025

Payment Deadline                                     :    1st of August 2025

Full Paper Submission                              :    25th of August 2025

Conference Day                                          :    1st – 4th of September 2025

• Keynote Speaker
  • H.E. Arief Havas Oegroseno
  • (Deputy Foreign Minister of the Republic of Indonesia)

• Speakers
  • Prof. I Gusti Ngurah Parikesit Widiatedja, S.H., M.Hum., LL.M., Ph.D. (Universitas Udayana)
    • Trump’s Unilateral Tariff Policy: Obliterating International Trade Law?
  • Dr. Su Wai Mon
    • (Research Fellow, Oceans Law and Policy at the NUS Centre for International Law) Unilateral Interpretation of Maritime Security Exceptions: Safeguarding Sovereignty or Undermining Legal Certainty
  • Prof. Dra. Sri Wartini, S.H., M.Hum., Ph.D. (Universitas Islam Indonesia)
    • Climate Change and State’s Unilateralism: A Critical Legal Analysis
  • Nguyen Thi Hong Yen, Ph.D. (Hanoi Law University)
    • Unfriendly State’s Unilateralism in the Development of International Law

• Moderator
  • Ms. Nur Gemilang Mahardhika, S.H., LL.M., M.H. (Universitas Islam Indonesia)

• Participants
  • All Indonesian lecturers of International Law (both members and non-members of ISILL), professional researchers, students, and other academics in law and legal studies worldwide.