NATO leaders won Donald Trump’s public endorsement of the alliance’s collective-defence guarantee, but little else was settled. The summit ended amid uncertainty over future U.S. troop commitments, defence funding, next year’s meeting and Europe’s ability to shoulder greater responsibility without Washington.

As doubts swirl over US President Donald Trump's commitment to protecting NATO, Europe needs to take more responsibility for its own defence. After decades of underinvestment by…

As talks swirl over U.S. President Donald Trump's commitment to NATO, both sides of the Atlantic now agree: Europe needs to step up and take more...