The senators have appeared on cable news programs, written op-eds and introduced bills pushing for more U.S. involvement abroad, and they’re building their national security credentials by taking every chance to travel to conflict zones…

The freshman trio has set itself apart from the isolationist policies espoused by some tea party classmates. One of the highest profile tea partiers in the Senate, Rand Paul of Kentucky, has called for slashing foreign aid. Paul and Sen. Mike Lee (R-Utah), another tea party sympathizer, introduced an unsuccessful resolution condemning President Barack Obama for failing to seek congressional approval before attacking Libya.

To Wisconsin Sen. Ron Johnson, one of 10 Republicans who backed the measure, the president’s action is unconstitutional and the U.S. mission in Libya unclear.

“I kind of like following the Constitution. It is Congress’s duty and responsibility to declare war, and I think at a minimum, the administration … should have come to Congress to get approval,” Johnson told POLITICO. “At this point, it’s just a muddle. We don’t have a clear objective. We haven’t stated it. It’s just not the way to conduct something like this.”