Just war theory, a centuries-old field of ethics, deals with how and when to start conflicts. It can also guide decisions ...

As peace talks continue in Berlin, what - if anything - could potentially change Putin's mind? And could Europe do anything ...

Ukraine's president continues ceasefire talks in Berlin with Trump envoys and European leaders, pressing for concrete security guarantees so Russia won't invade Ukraine again in the future.

Ukraine has relinquished its ambition of joining the NATO military alliance in exchange for Western security guarantees as a ...

President Trump pushes Kyiv to strike a quick deal with Moscow, but his Ukrainian counterpart wants security guarantees.

Ukraine’s president met with U.S. negotiators about plans to end the war with Russia. He said he would give up hopes of ...