Karim Kadim / AP Civilians inspect the aftermath of a car bomb attack in Baghdad, Iraq, on July 24. A bomb exploded near a Sunni mosque in Baghdad's southern Dora neighborhood on Tuesday, killing several people and wounding many more, police said.

As they watch Iraq’s mounting body count and potential slide into civil war, some Iraq War veterans are more intensely questioning why they went, what it all meant, and whether the deaths of 4,486 U.S. troops on that foreign soil were worth the permanent cost.

Others are concerned about the impact that Iraq’s summer unraveling may have on the morale of active-duty troops who once fought there and who now are trying to finish the equally grinding mission in Afghanistan.

And 10 years after the Iraq invasion, the deployment and re-deployments of 1.5 million Americans, the subsequent execution of ex-leader Saddam Hussein, the rise of new acronyms like IED and PTSD, and a jarring suicide epidemic, a portion of former Iraq War troops say the mental-health struggles faced by so many younger veterans may consequently deepen.

“You think about the guys who lost their lives in World War II, at least there was a higher purpose for risking your life,” said Andrew O’Brien, an Army convoy gunner who served in Iraq during 2008 and 2009, surviving an IED blast. He attempted suicide in 2010. “Now that I’m hearing about this, all I think about is the guys we lost in Iraq. It’s hard to not think that it meant nothing.”

O’Brien, 25, diagnosed with Post Traumatic Stress Disorder, just completed a six-week speaking tour during which he detailed his post-war experience as part of his suicide-prevention work. During his travels, he said he met dozens of Iraq veterans who are “still trying to figure out what happened out there,” who came home angry, confused, and depressed.

“This is just going to add a lot to that anger. It will increase risk. It will increase the possibility of people getting more upset and not handling it,” O’Brien said. “A lot of guys already were asking me: ‘What was the point? Why did my friend die but nothing is changing over there?’ Now, it’s not that nothing is changing; it’s changing but it’s getting worse. So I see them as thinking, I risked my life and I got shot, and I got blown up — for what?”

During July, almost 700 people in Iraq have been killed in militant attacks, including car bombs, ambushes and gun fights. The violence spike coincides with Sunday's escape by senior Al Qaeda leaders from Baghdad’s notorious Abu Ghraib prison. Reports estimate that between 250 and 500 militants fled their cells. The freeing of those militants adds to fears that the country is in the midst of another civil war as Kurds, Shiites and Sunnis have yet to find a stable way to share power.

Al Qaeda linked militants in Iraq staged an assault on Iraq's notorious Abu Ghraib prison freeing hundreds of militants from their cells. NBC's Richard Engel reports.

'It's frustrating to see this'

"Many troops in Afghanistan have also deployed to Iraq, so to see their hard work unraveling while their mission in another country is still in progress could be demoralizing," said Alex Horton, 28, a former specialist in the 3rd Stryker Brigade of Second Infantry Division who served a 15-month Iraq deployment from 2006 to 2007, during "the surge."

"Personally, it's frustrating to see this. We understood our mission was to create enough space for the Iraqi military and government to competently operate. That space was opened with the grit of American and Iraqi forces and measured in blood," Horton said. "In one of their biggest tests since the surge, the Iraqi military not only failed us, but their own people."

Some ex-service members hold fast to their old military mindset, still fixed squarely on the jobs they successfully accomplished in Iraq.

"It’s certainly tragic. But it doesn’t affect how I feel about what I did. I’m very proud of my service. We did everything we needed to do. Our mission was very specific and we knocked it out," said Derek Coy, 28, a former Marine aviation-supply specialist who deployed to Iraq for a year spanning parts of 2005 and 2006. "I imagine that after World War I, veterans felt the same way when Hitler rose.

"When you look at the bigger mission, yeah, it’s easy to get flustered, and you really think: Wow, we spent that much time?" Coy added. "For me, I don’t think there’s a direct correlation about what we did and what’s happening now. I don’t feel that I’m responsible for this."

But other Iraq veterans do feel like they contributed to the current political and social upheaval.

"What it makes me feel is deeper guilt," said Mike Prysner, an anti-war activist who, at 19, was part of the 2003 Army invasion. He served in Iraq for 12 months and left the service as a corporal.

"One of our roles was to shred their national identity. What is happening today is a direct result of the U.S. occupation's strategy," added Prysner, 30. "I remember the Iraqi government being setup along ethnic lines by the U.S. occupation. I remember arming certain ethnic groups to fight others. I'll live the rest of my life knowing I was a part of that."

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