At a Ron Paul rally during Tuesday’s Iowa caucus, Army Cpl. Jesse Thorsen stood behind a podium and, while in uniform, voiced his support of the Republican candidate.

“His foreign policy is, by far, hands down, better than any candidates out there,” he told a cheering crowd. “We don’t need to be picking fights overseas and I think everybody else knows that too.”

The move apparently violated military regulations that prohibit certain political activity.

Paul, an Air Force veteran, invited the soldier after a live CNN interview he had been conducting was cut short.

Paul Rieckhoff, founder of Iraq & Afghanistan Veterans of America, immediately sent out a tweet to point out the problem.

“Soldier who just spoke on behalf of Ron Paul is gonna be in some trouble,” he said. “Politics in uniform is a big no-go. And Paul should know better.”

He linked to a 2004 American Forces Press Service story highlighting political activity restrictions for Department of Defense employees: “Military members can attend only as spectators and not in uniform.”

Some on Twitter asked about the freedom of free speech, but Rieckhoff reminded them that service members are bound by the military justice system.

He expressed his views on politics and military with a tweet Wednesday morning:

“If we learned one thing in Iowa last night, it's that vets will be one of the most popular politics props of 2012.”