Tuesday night's Republican debate revealed a deep rift in the Republican party over how to deal with Middle East dictators a decade after George W. Bush's neoconservative call for aggressively promoting American-style democracy in the region.

As the GOP candidates offered similar plans for fighting the Islamic State, a richer argument emerged over America's foreign policy priorities — one evident in the clash between Marco Rubio and Ted Cruz over the fate of Syrian dictator Bashar Assad and other Middle East strongmen opposed to radical Islamists.


Cruz, playing the role of foreign policy realist, said that President Barack Obama had left America less secure by pushing for the ouster of Arab dictators, including Assad, whom Obama insists must leave power. "If we topple Assad, the result will be ISIS will take over Syria and it will worsen U.S. national security interests," the Texas senator said.

But he also trained his fire on his emerging rival, Rubio, tying him to Obama's policies in the region and offering a succinct summation of the GOP's post-Bush divide.

“One of the problems with Marco’s foreign policy is he has far too often supported Hillary Clinton and Barack Obama undermining governments in the Middle East that have helped radical Islamic terrorists," Cruz said. "We need to focus on killing the bad guys, not getting stuck in Middle Eastern civil wars that don’t keep America safe.”

Rubio backed Obama's 2011 military intervention in Libya, which helped to topple that country's dictator, Muammar Qaddafi, and applauded when Egyptian President Hosni Mubarak left power under pressure from Obama earlier that year.

The Florida senator's full-throated support for human rights and democracy echoes, to many Republican ears, Bush's grandiose, transform-the-Middle-East philosophy. Rubio has consulted with former key Bush advisers, including Elliott Abrams, a former Bush White House aide who specialized in democracy promotion, and the senator's longtime top foreign policy aide, Jamie Fly, has close ties in neoconservative circles.

Responding to Cruz, Rubio said he would not "shed a tear" if Assad were toppled, noting that the Syrian dictator is allied with the Iranian-backed terrorist group Hezbollah and enabled attacks on Americans in Iraq during the U.S. occupation of that country.

But Cruz, whose conservative bloc of supporters is suspicious of America's ability to reshape the world in its image, showed no remorse for saying that the U.S. would be better off working with Assad — a man whose regime has used chemical weapons against civilians and is responsible for wanton killing and torture — than seeking his ouster.

Cruz said the toppling of Assad would be part of a trifecta of Obama mistakes.

"Let's go back to the beginning of the Obama administration, when Hillary Clinton and Barack Obama led NATO in toppling the government in Libya," he said in his opening exchange with moderator Wolf Blitzer. "They did it because they wanted to promote democracy. A number of Republicans supported them. The result of that — and we were told then that there were these moderate rebels that would take over. Well, the result is, Libya is now a terrorist war zone run by jihadists."

In Egypt, Cruz noted, the Obama administration joined with Republicans to topple Hosni Mubarak, a secular autocrat "who had been a reliable ally of the United States" and was succeeded by Mohamed Morsi, a leader of the Muslim Brotherhood, which Cruz called "a terrorist organization."

Despite their faults, Qaddafi and Mubarak "were at least assisting us in fighting radical Islamic terrorists," Cruz said. And in a subtle dig at Jeb Bush, Cruz added that the Middle East would be less of a threat to the United States if Saddam Hussein were still in power.

"Instead of being a Woodrow Wilson democracy promoter, we ought to be hunting down our enemies," Cruz said.

That was another shot at Rubio: Wilson's talk of making the world "safe for democracy" in the World War I era has been a benchmark for foreign policy idealists who believe the U.S. has a duty to promote its values abroad. Rubio has appealed to that sentiment by calling for "moral clarity regarding America's core values," and vowing to invite dissidents from China, Cuba and Iran to attend his inauguration.

But many Americans have come to equate democracy promotion with the Iraq war, and the idea has lost its luster within the GOP.

Rubio made no moral case for his foreign policy on Tuesday night. He cast his Libya position not as an act of idealism but security, noting that Qaddafi had killed dozens of Americans through terrorist attacks. (At the time of Obama's intervention, Rubio struck a somewhat different tone: Libyans had "legitimate demands for a better future," he argued, adding that the U.S. "has unique moral obligations and responsibilities" around the world.)

Instead, Rubio acknowledged, "we will have to work around the world with less than ideal governments," citing Jordan and Saudi Arabia, both internally repressive U.S. allies. But he added that he would not mind seeing "anti-American" dictators like Assad fall.

Donald Trump did not take a clear position on Assad's fate, but the front-running mogul complained — in his most forceful moment of the night — that the U.S. has spent $4 trillion "trying to topple various people," adding that the money would have been better spent on infrastructure like roads and bridges in the U.S. (The source of Trump's $4 trillion figure was not clear. He also used the figures $3 trillion and $5 trillion.) "We have done a tremendous disservice to humanity. And for what? It's a mess," Trump said.

Ben Carson echoed that view, saying that "we need to start thinking about the needs of the American people before we go and solve everybody else's problems. The fact of the matter is, is that the Middle East has been in turmoil for thousands of years. For us to think that we're going to in there and fix that with a couple of little bombs and a few little decorations is relatively foolish."

Those comments would have been anathema during the Bush era, when Republican partisans mocked Democrats for insisting that funding for the Iraq war should go to domestic priorities — that the U.S. should build schools in America, not Iraq.

Carly Fiorina, the former Hewlett-Packard CEO, appeared to agree, pouncing on Trump after his remarks about infrastructure.

"That's exactly what President Obama says," she fired back. "I'm amazed to hear that from a Republican presidential candidate."

But it's not George W. Bush's party anymore.