Donald Trump on Jeb Bush Attacks: 'I Think He Had No Choice'

— -- Republican presidential front-runner Donald Trump said he is not surprised by the recent attacks by former Florida Gov. Jeb Bush.

"Well, I think he had no choice,” the real estate mogul told ABC News' George Stephanopoulos this morning on "Good Morning America."

“It seems to be backfiring, based on the polls. It seems to be somewhat backfiring on Jeb," Trump added. "So far everyone that has attacked me has gone down. Let’s see what happens."

Bush’s new video, released Tuesday on his Twitter account @JebBush, entitled “The Real Donald Trump,” is almost entirely comprised of old interview clips that Trump participated in.

It begins with Trump speaking these words [from 1999], "I lived in New York City, in Manhattan all my life so my views are a little different than if I lived in Iowa.”

You then hear Trump say “I am very pro-choice” and proclaim that he thinks Hillary Clinton would do a good job in Iran negotiations.

CNN’s Wolf Blitzer asks he if identifies more as a Democrat or a Republican. Trump responds, “you'd be shocked if I said that, in many cases, I probably identify more as a Democrat.”

Trump told Stephanopoulos today that when he was solely focused on business, he had to play nice. “That was my obligation. ... They termed me a world-class businessman," he said.

The GOP front-runner also responded to one portion of the Bush ad in which he says he doesn’t know why he is a Republican. “They [Republicans] had some ideas that were different than my ideas, and many Republicans were saying [then] they didn’t know why they were Republican.”

Trump is still at the top of all the most recent national polls. He tied with neurosurgeon Dr. Ben Carson in a new Iowa poll released by Monmouth University on Monday. "I like Ben a lot, he’s a good guy but he’s been spending a tremendous amount of advertising money in Iowa," Trump said.

Trump is off the campaign trail this week before the long Labor Day weekend. Next week, he flies to Washington to join fellow GOP candidate Sen. Ted Cruz, R-Texas, to protest the Iran nuclear deal. Trump said he does not support the deal, telling "GMA" it was negotiated by “stupid, incompetent people. There is something wrong with them.”

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