Story highlights Obama this week became the first sitting president to visit Hiroshima

"Does President Obama ever discuss the sneak attack on Pearl Harbor while he's in Japan?" Trump tweeted

"Does President Obama ever discuss the sneak attack on Pearl Harbor while he's in Japan? Thousands of American lives lost. #MDW," tweeted Trump, the presumptive Republican nominee.

Does President Obama ever discuss the sneak attack on Pearl Harbor while he's in Japan? Thousands of American lives lost. #MDW — Donald J. Trump (@realDonaldTrump) May 28, 2016

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.

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"Why do we come to this place, to Hiroshima? We come to ponder the terrible forces unleashed in the not-so-distant past. We come to mourn the dead ... their souls speak to us and ask us to look inward. To take stock of who we are and what we might become," Obama said during his visit to the city's Peace Memorial Park.

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