Allied Nations

Turkey's commitment to acquiring Russia's S-400 anti-air system is unacceptable, Air Force Lt. Gen. Tod Wolters said.

The U.S. has halted shipments after the NATO ally refused to back down from its intent to purchase the Russian-made S-400.

Dunford said he's worked hard to improve relations with NATO-allied Turkey, but the S-400s could be a deal-breaker.

Gen. Tod Wolters would become the fourth Air Force officer to hold the NATO post.

The U.S. Air Force has sent B-52 Stratofortress bombers to the United Kingdom for strategic missions in Europe, according to...

As Russia and China make inroads in the region, U.S. officials are participating more across Latin America.

The prospect of the Arctic Ocean emerging as a theater of military rivalry will create new challenges for the U.S. and NATO.

Close friend Bill Cohen said the defense secretary agonized over his decision.

Defense Secretary Jim Mattis resigned Thursday, saying he'll stay until the end of February.

The sale is unconfirmed, as the country already has agreed to buy Russia's S-400 "F-35 Killer" system.