Defense and Security

Security Alliances

  • NATO (North Atlantic Treaty Organization)
    What Is NATO?
    The alliance is bolstering its military deterrent in Europe amid Russia’s invasion of Ukraine and could be poised for another major expansion.
  • Japan
    The U.S.-Japan Security Alliance
    The alliance with Japan has been the cornerstone of U.S. security policy in East Asia for decades. Now, Japan’s role in global security is growing as challenges from China and North Korea mount.
  • Mexico
    Experts argue that Mexico affects daily life in the United States more than any other country. For years, U.S. and Mexican officials have attempted to tackle immigration, trade, and security challenges, and their success has depended on cooperation. With so much at stake, Why It Matters investigates the complex relationship and the factors that threaten it.   

Experts in this Topic

Charles A. Kupchan
Charles A. Kupchan

Senior Fellow

Manjari Chatterjee Miller
Manjari Chatterjee Miller

Senior Fellow for India, Pakistan, and South Asia

Scott A. Snyder
Scott A. Snyder

Senior Fellow for Korea Studies and Director of the Program on U.S.-Korea Policy