It’s a wonder so many Bush aides are open to working for Trump considering the animosity between him and Bush.

Trump has accused the former president of lying about weapons of mass destruction to invade Iraq. Trump also insists, falsely, that he personally never supported invading the Arab country. Many Trump allies despise the Bush crowd, viewing them as classic establishment types who foolishly got the U.S. entangled in conflicts overseas. And Trump also repeatedly mocked Bush’s brother, Jeb, one of his rivals for the GOP presidential nomination, as “low energy.”

Several top-ranking Bush aides, including former Homeland Security chief Michael Chertoff, have denounced Trump. The former president himself left his ballot blank rather than vote for the blustery Republican nominee. Still, plenty of Bush acolytes, including Cheney and former Defense Secretary Donald Rumsfeld, have endorsed Trump. And since last week’s election, at least five former Bush aides have been reported as possible picks for Trump’s Cabinet or other top gigs.

They include fairly well-regarded figures such as Stephen Hadley, a Bush national security adviser, and much-vilified ones, such as Jose Rodriguez, the CIA official who developed interrogation programs for terrorism suspects. Other names include Zalmay Khalilzad, who served in multiple capacities, including ambassador to Iraq; John Bolton, a hawkish former U.N. envoy who’s called for bombing Iran; and Fran Townsend, Bush’s homeland security adviser.

At this stage, it’s too early to say if any of these Bush officials will land in the Trump administration. It’s a trial balloon period, anyway, with names being leaked to gauge public reaction. Trump’s positions on foreign policy also are often vague and inconsistent, and his choices for top jobs can be anything but conventional. (Attempts to reach his aides for comment were not immediately successful.)

But because numerous Republican national security elites have spoken out against Trump, the ranks of job candidates are thinner than normal. And considering the Bush era was the last time the GOP ran the White House, it’s still the Trump transition team’s best hunting ground for executive branch staffers.

“There’s a lot of expertise embodied in those individuals, and if you want to assemble the best team, some of these are names that you would consider,” said Peter Feaver, a former national security aide to Bush.

Trump has an isolationist streak — the kind that leads him to say (now anyway) that the U.S. should not have invaded Iraq. And he appears to lack the concern about human rights and democracy promotion that fueled much of the Bush and neoconservative approach to the world. But Trump does appear bent on keeping up the fight against Islamist militants. And Bush aides, who had to deal with the fallout from the Sept. 11, 2001, attacks, could be appealing job candidates in that sense.

The problem is that Trump has made some statements that could revive some of the ugliest debates that gripped the 2000s — debates many people thought were settled.

Trump has called for using waterboarding and measures “a hell of a lot worse” on terrorism suspects. Even Bush phased out the use of such tactics during his final years as president after much national soul-searching over torture. (Trump also has called for killing the families of terrorists, a position generally understood as a war crime.)

The incoming president also said things that raise doubts about his commitment to multinational institutions.

He’s suggested that the U.S. won’t fulfill its obligation to aid fellow NATO members under attack if they are not paying enough into the overall alliance’s defense. Few Republicans from the Bush administration would likely agree with such a stance, even as many in both political parties agree some European countries need to spend more on defense. Trump also has questioned whether the U.S. is spending too much on the United Nations and suggested he’d like to see a smaller version of the world body — one without the United States.

The future of Guantanamo Bay, a hugely divisive issue during the Bush years, also could be at stake.

Bush hoped to ultimately close the prison, where dozens of terrorism suspects are still being held. Obama tried to shut it down but ran into resistance from Congress — he’s managed to shrink the population instead. Trump has not only criticized Obama’s efforts, he’s said he thinks U.S. citizens should be tried at Guantanamo, too.

If Trump were to be expansive in his use of executive power, another hot-button topic, he could get support from Bush aides, either inside or outside his administration, who have long argued that the president has far more authority than many legal scholars believe he does. But Trump would have Obama to thank on that front, too. Obama, facing a recalcitrant GOP, used executive actions on numerous fronts with little to no congressional input.

The possibility of re-litigating some of these fights can’t be dismissed, said Susan Hennessey, managing editor of the Lawfare blog, which deals with national security issues. “These are incredibly significant questions, not just about what kind of President Trump might be, but also what kind of country are we, what lessons have we learned?” she said.

As with so much else, much will depend on whom Trump chooses to work for him. Some Bush acolytes, having had significant experience, may actually be able to hold back some of the Manhattan billionaire’s worst tendencies. But there’s also the possibility that the most moderate Bush aides are in the Never Trump camp, and that those who do join the new president’s administration will back his iffy instincts.

“There is a very great danger that Donald Trump will not be able to staff a competent national security team, and there is also a great danger that the team he assembles will aspire to eclipse the worst aspirations and activities of the early Bush administration in the national security arena,” said Benjamin Wittes, a senior fellow at the Brookings Institution.

Trump, who has no military or governing experience, could also decide he has little interest in foreign affairs, leaving Pence to fill the vacuum.

The vice president-elect, a former member of the House Foreign Affairs Committee, at times comes across as far more hawkish and interventionist than his boss. He’s called for standing up to Russia, even if it means intervening in Syria, while Trump has spoken about trying to get along with Moscow as much as possible.

Pence’s choice of Cheney as a role model suggests he is keen on being an active, powerful vice president. Already, he and his backers have taken over the Trump transition team, essentially pushing out the group loyal to New Jersey Gov. Chris Christie; Cheney ran Bush’s transition in a top-down way Pence is expected to echo. But if Pence is too aggressive, he could be painted as a puppet-master, the same way Cheney was cast during the Bush years.

One of the challenges facing Bush administration officials who seek to join the Trump team could be the Senate confirmation process. Democrats, though still in the minority, could agitate over each person’s role in the invasion of Iraq and the chaos that followed, not to mention questions about their positions on torture and other controversial topics.

“I’ll ask from those who seek Senate confirmation about their commitment on human rights,” Sen. Ben Cardin, the ranking Democrat on the Senate Foreign Relations Committee, pledged to POLITICO in a recent interview.

The reality is that Republicans across the board believe America has grown weaker on the world stage under Obama. And many of those who served in the Bush administration disagree with critics who’ve painted their past efforts as failures. So if they’re going to join a Trump administration, it’s probably not out of a desire for public redemption, but more out of a sense of public service.

Bush aides “actually think ‘We did a lot of good for the country. We made mistakes. Not everything went perfectly but the critique of the Bush administration is a cartoon,’” Feaver said.