Washington, May 30 (RHC)-- U.S presidential candidate Donald Trump has questioned why President Barack Obama didn't mention the Japanese attack on Pearl Harbor during his trip this week to Japan.

Obama did not publicly mention the surprise 1941 attack that pulled the U.S. into World War II while on his historic trip to Japan this week, during which he became the first sitting U.S. president to visit Hiroshima.  He used the visit to discuss the threat of nuclear weapons.

The White House didn't immediately comment on Trump's tweet over the weekend.

Trump supporter Sarah Palin also criticized the trip, calling it part of the President's "apology lap."  Palin, speaking at a Trump rally in San Diego, said Obama's trip to Hiroshima was "dissing our vets."