Mr. Trump roused his Polish hosts by recounting the country’s history of resistance to invaders, including Nazi Germany and the Soviet Union. But he said nothing about the right-wing government’s crackdown on judges and journalists and its refusal to accept more migrants, policies that have upset European Union leaders. He instead praised Poland as a defender of liberty in the face of existential threats.

“The fundamental question of our time is whether the West has the will to survive,” he said. “Do we have the confidence in our values to defend them at any cost? Do we have enough respect for our citizens to protect our borders? Do we have the desire and the courage to preserve our civilization in the face of those who would subvert and destroy it?”