The unprecedented Iranian attack on Israel presents U.S. officials with mounting challenges in trying to contain the conflict and maintain a deterrence against Iran and its allies.

The Iranian regime’s first direct attack on Israeli territory could trigger further exchanges between the two sides and raises the most serious risk of regionwide conflict since the Israel-Hamas war …

Houthi attacks against commercial ships in the Red Sea have upended global shipping. The disruptions could soon ripple through the global economy.

The United States and South Korea should pursue an expanded nuclear agreement that supports the production of civilian nuclear power and enhances extended deterrence against the North Korean threat. …

Russia’s threat to deploy tactical nuclear weapons in Belarus has raised the specter of a new nuclear standoff with the United States and its allies in Europe. It also draws new attention to how such…