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Jeb Bush criticized Donald Trump in an interview that aired on MSNBC on Monday

Bush said if Trump wants to become President, he should brush up on nuclear triad

CNN  — 

Jeb Bush insists that Donald Trump will not win in 2016, but says if he’s “aspiring” to be the next President, “the dude ought to try to figure out what the nuclear triad is.”

In an interview airing on MSNBC on Monday, Bush pushed back when asked if he was beginning to acknowledge the possibility Trump could win, after comments he made at a town hall seemed to indicate a shift in tone after months of maintaining Trump would lose.

Bush said Trump “sure as heck better [learn about the nuclear triad] if he’s going to be the next president.”

“Is there a sense that maybe you are saying that this could happen?” host Mika Brzezinski asked.

“No, no I made a mistake if I said that. He’s not going to be President,” Bush laughed. “But he should, if he’s aspiring to the presidency – the dude ought to try to figure out what the nuclear triad is. Come on.”

RELATED: 3 things to know about that nuclear triad

The nuclear triad has been a thorny topic for Trump throughout the campaign.

At CNN’s Republican presidential debate in December, Trump appeared confused when asked by Hugh Hewitt about U.S. nuclear capability and which part of the triad he would prioritize, giving a meandering response before saying, “For me, nuclear, the power, the devastation, is very important to me.”

GOP rivals have since tried to use the exchange to knock Trump’s qualifications for president and raise questions about his understanding of policy topics like the nuclear triad.