He might be standing, but he’s having hard time singing. President Trump appeared to forget the lyrics to “God Bless America” during a White House event Tuesday meant to prove how patriotic he is. Trump was caught on video singing every other word to the national hymn as a military chorus boomed behind him. On three occasions, Trump gave up singing all together and let the uniform-clad men around him do the vocalizing. A White House spokesman did not return a request for comment from the Daily News. The last-minute “Celebration of America” event was put together after Trump cancelled...