Tony Blair On ISIS: Don't Rule Out Ground Troops

As the U.S. begins yet another military campaign in Iraq, a key architect of the West's previous invasion of the country is speaking out about how to defeat the militant group ISIS.

TONY BLAIR ON CNN: "You can hem these people in and contain them by air power, but if you want to defeat them, there will have to be someone's boots on the ground."

Former British Prime Minister Tony Blair has published a lengthy essay on his website outlining seven principles for combating Islamic extremism. One of the major takeaways from the essay — Blair writes: "I accept fully there is no appetite for ground engagement in the West. But we should not rule it out in the future if it is absolutely necessary."

Blair, of course, was one of the main world leaders spearheading the Western coalition behind the 2003 invasion of Iraq — a fact that either helps or hurts his case, depending on your perspective.

But the former prime minister's words do address one of the most difficult questions about the military campaign against ISIS: Will the U.S. need to send ground troops into the country?

Currently, the U.S. strategy to combat ISIS revolves around targeted airstrikes, which have seen limited success in pushing back the militants. But critics of Obama's plan say airstrikes alone won't be enough to accomplish the administration's stated goal of destroying ISIS. (Video via U.S. Central Command)

President Obama has been adamant about not sending U.S. troops back into Iraq.

OBAMA VIA THE WHITE HOUSE: "As your commander in chief, I will not commit you and the rest of our armed forces to fighting another ground war in Iraq."

But key military officials and members of Congress are saying it can't be ruled out.

GEN. MARTIN DEMPSEY VIA C-SPAN: "If we reach the point where I believe our advisers should accompany Iraq troops on attacks against specific ISIL targets, I'll recommend that to the president."

REP. PETER KING ON FOX NEWS: "I don't see how ultimately we can avoid putting combat troops on the ground in some capacity."

Currently, the administration's policy relies on supporting moderate fighters resisting ISIS, like the Kurdish peshmerga and the Free Syrian Army, alongside a broad international coalition, which the White House hopes includes Arab powers in the region. (Video via ITV)

Blair's essay also discussed the ideology behind violent extremism along with the importance of education to combat that extremism.

This video includes images from Getty Images.