The release of a member of the U.S. military held captive by one of our nation's enemies should be a cause for celebration. But the circumstances of Army Sgt. Bowe Bergdahl's liberation after nearly five years of being held by the Taliban in Afghanistan are also cause for serious concerns.

President Barack Obama announced Sgt. Bergdahl's "recovery" Saturday. According to Politico, the White House conspicuously avoided using the terms "release," "transfer" or "swap."

But this clearly was a trade in which the U.S. freed five terror detainees at Guantanamo to obtain the freedom of one American soldier.

And the president's move to bring home our final captive in Afghanistan appears to violate last year's legislation that required him to give Congress 30 days' notification before releasing any Guantanamo prisoners.

But even more troubling than that question of legality: This terrorists-for-hostage deal conveys a dangerous signal to foes - and friends.

Sen. Lindsey Graham, R-S.C., expressed that justified alarm Monday in a letter to Senate Armed Services Committee Chairman Carl Levin, D-Mich., and the panel's ranking Republican member, Sen. James Inhofe of Oklahoma, requesting "an immediate hearing" on that exchange of prisoners.

From Sen. Graham's letter: "The five terrorists released were the hardest of the hard-core. They held positions of great importance within the hard-core anti-American Taliban, including the Chief of Staff of the Taliban Army and the Taliban Deputy Minister of Intelligence. They have American blood on their hands and surely as night follows day they will return to the fight. In effect, we released the 'Taliban Dream Team.' "

And encouraging terrorists to take Americans hostage is a nightmare scenario.