Washington ? President Bush and British Prime Minister Tony Blair acknowledged difficult times in the Iraq war they launched together in 2003, but both vowed to keep troops there until the new Iraqi government takes hold. Both admitted making costly mistakes.

“Despite setbacks and missteps, I strongly believe we did and are doing the right thing,” Bush said Thursday evening in a White House news conference with Blair. “Not everything has turned out the way we hoped.”

For his part, Blair declared that after a meeting earlier this week with Iraq’s new prime minister, “I came away thinking the challenge is still immense, but I also came away thinking more certain than ever that we should rise to it.”

In unusually introspective comments, Bush said he regrets his cowboy rhetoric the wake of the Sept. 11, 2001, terror attacks early in the war such as his “wanted dead or alive” and “bring ’em on.”

“In certain parts of the world, it was misinterpreted.”

He also cited the mistreatment of Iraqi prisoners at the U.S.-run Abu Ghraib prison near Baghdad. “We’ve been paying for that for a long time,” Bush said.

Blair regretted the way that Saddam Hussein’s political allies were purged from the Iraqi military and government soon after the fall of Baghdad. Critics have said the sudden purge left a security vacuum in Iraq and encouraged former regime loyalists to take up arms against the newly installed government.

Blair also said allies seriously underestimated the insurgency.

“It should have been very obvious to us” from the beginning, Blair said.