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One of the recurring themes in the Republican presidential debates has been Jeb Bush trying to attack Donald Trump and Trump destroying him. During Tuesday's CNN debate, Trump and Bush got into a sparring match again, this time over national security and immigration. Trump was accusing Bush of being soft on immigration, when Bush jumped in to say that Trump had said ISIS isn't America's problem. Trump tried to bash Bush into quieting down, and Bush smiled and said, "A little of your own medicine, there, Donald."

"I know you're trying to build up your own energy, Jeb, but it is not working very well," Trump retorted, as host Wolf Blitzer tried to mediate. "Donald, you're not going to be able to insult your way to the presidency — it's not going to happen," Bush said, getting his biggest applause line of the night. "Leadership is not about insulting people and disparaging people. Leadership is about creating a serious strategy to deal with the threat of our time."

Trump tried to get in the last word: "With Jeb's attitude, we will never be great again." But for probably the first time, Bush had already won the exchange.