Donald Trump is continuing to thrash George W. Bush over his handling of 9/11 (and crushing JEB! who is in single digits, and everyone else in latest SC poll)

(Business Insider) - At a press conference on Monday, Donald Trump doubled down on his claims that former President George W. Bush did not keep the country safe because of the September 11, 2001, terrorist attacks.

"I've heard for years he kept the country safe after 9/11," Trump said. "What does that mean, after? What about during 9/11? I was there. I lost a lot of friends that were killed in that building. The worst attack ever in this country, it was during his presidency. ... By the way, after that, we did ok. That's meaning the team scored 19 runs in the first inning, but after that we played well. I don't think so."

Trump is campaigning in South Carolina ahead of the state's primary contest later this week. The real-estate mogul, who is a front-runner in the race for the Republican presidential nomination, has been touting his opposition to the Iraq War, whichsome say that Trump has misrepresented.

Trump has used his supposed opposition to the 2003 invasion of Iraq to attack former Florida Gov. Jeb Bush (R), whose brother was the president when the 9/11 terrorist attacks happened. He said at the Republican debate on Saturday night that "the World Trade Center came down during your brother's reign."

He went even further than that at the press conference, implying that the US should not have toppled former Iraqi President Saddam Hussein because he went after terrorists in Iraq.

"Saddam Hussein was a bad guy. But one thing about him, he killed terrorists," Trump said. "Now Iraq is Harvard for terrorism. You want to become a terrorist? You go to Iraq. Saddam Hussein understood, and he killed terrorists."

Trump also said that the US "shouldn't have been" in Iraq and "shouldn't have gotten out the way we got out."

"If the president went to the beach, we would have been better off, believe me," Trump said. Read more.

Meanwhile, Donald Trump is the clear front-runner heading into Saturday's South Carolina Republican primary.

A new Public Policy Polling surveyreleased Tuesday found Trump leading in the crucial third-nominating state by a large margin.

According to the poll, 35% of likely Republican voters supported Trump. Sens. Marco Rubio (R-Florida) and Ted Cruz (R-Texas) tied for second with 18%.

Ohio Gov. John Kasich (R) trailed in fourth with 10%, while former Florida Gov. Jeb Bush (R) and retired neurosurgeon Ben Carson each captured 7% of the support. Read more.