A profile of the international terrorist network that the United States has singled out as the most serious threat to U.S. security.

Kim Jong-il’s death has prompted discussion about the future of the isolated country and its nuclear weapons program. Experts cited in this CFR Backgrounder believe a post-Kim regime in North Korea w…

The longstanding U.S.-South Korea alliance, created as a bulwark against a communist North Korea, has expanded to include tighter trade ties and cooperation on global issues from climate change to in…

Ayman al-Zawahiri, now America’s most wanted terrorist, took over as the head of al-Qaeda in June 2011 after the killing of erstwhile head Osama bin Laden.

Pakistan’s intelligence agency, the ISI, faces persistent accusations of links to terrorism, despite repeated denials.