'It is the president' who decides on going to war, regardless of John Bolton’s rhetoric: National security expert

A former national security adviser said that despite concerns that President Donald Trump's new adviser, John Bolton, might "take the country to war," any such decision would lay with the president.

There is "a lot of concern about whether Bolton will take the country to war" in his new role as Trump's national security adviser, Stephen Hadley, a national security adviser under President George W. Bush, said to ABC News "This Week" Co-Anchor Martha Raddatz on Sunday.

But, Hadley said, "It is the president that makes those decisions."

Bolton, who served as U.S. ambassador to the United Nations in the Bush administration with Hadley, was named by Trump to his top national security post to replace H.R. McMaster, who resigned last week. He is known as a foreign-policy hawk who has often advocated for military action over diplomacy.

Another former high-level government official, Ret. Adm. Mike Mullen, appearing with Hadley on "This Week," agreed that Bolton's work as national security adviser will be in service to Trump, not the other way around.

"He's working for the president," said Mullen, a former chairman of the Joint Chiefs of Staff under both presidents Bush and Obama. "The president is clearly not going to be working for him. So it's going to be the president's views that I think Mr. Bolton will actually in the end execute."

However, Mullen said, if Bolton’s past rhetoric were taken at face value, he’d have concerns.

“I am concerned, if I believe Mr. Bolton's rhetoric where he's talked about pre-emptive strike or even pre-emptive war in North Korea,” Mullen said. “He's obviously very strongly opposed to the nuclear deal in Iran.”

Mullen added, "I wonder, you know, are we going backwards in terms of those countries ... the ones that still present huge challenges for us" such as Iran and North Korea, and will Bolton lead to "a much more militaristic" approach.

Hadley said he doesn't agree with some of Bolton's stated views, but added that tough rhetoric from President Trump may have led to progress on North Korea by getting China involved.

“I think the rhetoric out of John Bolton has been a little bit extreme for my taste," Hadley said. "But we have to make this point, give this to the administration, that while they were criticized for too much rattling of the sword with respect to North Korea, it did get China's attention, it did convince China that the status quo was not sustainable" on North Korea's nuclear program.

Hadley also said of Bolton, “John is a very smart, very experienced, very tough guy," adding that the president deserves a national security adviser he is comfortable with.

“The president is the person elected by the American people to set foreign policy,” Hadley said. “He deserves people around him who think the same way.”