WARSAW (Reuters) – A plane carrying U.S. troops landed in Poland on Sunday, a Reuters witness said, as Washington reinforces its NATO allies in Eastern Europe amid a Russian military build-up on Ukraine’s border. U.S. President Joe Biden on Wednesday ordered nearly 3,000 extra troops to Poland and Romania, as Washington moves to reassure jittery NATO allies. The Pentagon said that around 1,700 service members, mainly from the 82nd Airborne Division, would deploy from Fort Bragg, North Carolina, to Poland. Sunday’s arrival of the C17 aircraft followed a plane carrying the commanding general of …