How Donald Trump Is Turning on His Fellow Republicans Here are the biggest targets of Trump’s recent backlash.

 -- It’s no surprise when GOP presidential contenders aim their attacks at their Democratic rivals, but recently Donald Trump has been engaging in friendly fire.

The real estate mogul may be running for the Republican nomination, but that doesn’t mean that his fellow GOP candidates or his party’s leadership are off limits. Trump hasn’t just taken aim at his fellow White House contenders. In recent days, he’s gone up against some of the pivotal bedrocks of his party, including former President George W. Bush and the Republican National Committee itself.

Here are a few of the big targets of Trump’s recent backlash:

The Bush Family Dynasty

Over the last three decades of Republican politics, there may be no bigger influence than the Bush family, but that doesn't make them immune from Trump's insults. Recently, Trump turned his attacks from his presidential rival, Jeb Bush, toward Jeb's brother, George W. Bush.

“George Bush made a mistake. We can make mistakes. But that one was a beauty. We should have never been in Iraq. We have destabilized the Middle East,” Trump said during Saturday’s Republican debate while blaming George W. Bush for the Iraq War.

"You do whatever you want," Trump said to Jeb Bush. "You call it whatever you want. I wanna tell you. They lied. They said there were weapons of mass destruction, there were none. And they knew there were none. There were no weapons of mass destruction."

The Republican National Committee

Without explicitly saying so, Trump is floating the idea of a third party run again. It’s a move Trump threatened to do last summer before the RNC made every 2016 GOP candidate sign a pledge to support the eventual nominee and not run under a third party.

“The RNC better get its act together because you know I signed a pledge but that pledge isn’t being honored by them,” Trump said Monday at a town hall in Mount Pleasant, South Carolina.

Trump feels the RNC is in “default of their pledge” by filling Saturday’s GOP debate in South Carolina with “lobbyists and special interests.” Sean Spicer tweeted that 600 tickets were divided equally between all the candidates on stage, 10 RNC donors, and approximately 300 GOP grassroots and elected officials.

The business mogul also criticized the RNC last Saturday for sending out a fundraising email with his name on it and told supporters not to contribute to the RNC.

Trump has been poking fun again at the Florida senator for his perspiration tendencies.

“Marco Rubio, who stood with me, he was with me when he had the meltdown, and I’m telling you, it wasn't a pretty sight. No, he was standing right there, no, he was soaking wet, I’m telling you. He was wet. I say, 'What the hell’s going on over here?'" Trump said of Rubio at a campaign event in Greenville, South Carolina.

"I thought he just came out of a swimming pool, he was soaking. I said, 'Look! Wow.' I said, "Are you okay?'" he added.

Trump continued: "Can you imagine Putin sitting there waiting for the meeting and this guy walks in and he is like a wreck."

Trump is escalating his attacks on Cruz, threatening the Texas senator with a lawsuit if he doesn’t pull his recent ads and stop the attacks on Trump’s record.

"I’m thinking about it very seriously," Trump told ABC News' George Stephanopoulos on "Good Morning America" today of suing Cruz. "I’ve never dealt with anybody who lies like him."

In Greenville, Trump also called Cruz an “unstable guy” and even questioned whether Cruz is truly a Christian.

Trump sees the lawsuit against Cruz as “a favor” because he would be filing early and “the Democrats are going to file it, anyway.”

Eminent Domain

Trump’s stance on eminent domain, that is, the right of the government to seize private property for public use, strays from the conventional belief of the right.

“You wouldn’t have 10 feet of that pipeline if it weren’t for eminent domain. Because that pipeline goes from Canada -- the great birthplace of Ted Cruz,” Trump said in Farmington, New Hampshire, before the Iowa caucuses. Bush and Cruz have both jumped on Trump for saying this.

Trump then clarified Monday, saying, ”I don’t like eminent domain but you need road, you need a highway.”