WASHINGTON-Sen. John McCain, whose failed challenge to Barack Obama in the 2008 presidential election still rankles fellow Republicans, is back in harness as his party's chief Obama scold and bete noire.
The administration's decision to swap that American soldier held for five years for five high-quality Taliban members released from the Guantanamo detainee prison has McCain fiercely at the president's heels again.
As a former prisoner of war in North Vietnam, the fiery Arizonan has paired the episode with the 2012 terrorist attack on the U.S. consulate in Benghazi for another round of casting the Obama administration as incompetent and feckless in the conduct of foreign policy.
While joining the broad chorus of relief that Sgt. Bowe Bergdahl has been released, McCain has also led the blowback among many fellow conservatives and military veterans questioning the swap. They see it as unjustified, dangerous, or in violation of a requirement to give Congress a month's advance notice, or all three.
Further complicating the matter are the circumstances of Bergdahl's departure from his base in Afghanistan in 2009 and his ostensible capture by the Taliban. Some doubters have characterized it as a desertion that itself would require U.S. prosecution.
To critics who've deplored what they called negotiations for release of a "hostage" contrary to U.S. policy, Secretary of Defense Chuck Hagel on "Face the Nation" last Sunday declared that Bergdahl was a "prisoner of war" for whom such negotiation was legal and proper.
He cited concern over about the soldier's health as a particular imperative for action.
McCain has also placed himself in the forefront of the Republican assault on President Obama's tardy response to the Veterans Administration scandal, in which thousands of former servicemen have had to wait months and even years to obtain medical care to which they are entitled.
The Arizonan was among many senators who called on Obama to take decisive action prior to the eventual "resignation" of retired Gen. Eric Shinseki, another decorated Vietnam War veteran, as his Secretary of Veterans Affairs.
McCain and frequent sidekick Sen. Lindsey Graham, R-South Carolina, a former Army lawyer, have relentlessly held Obama's feet to the fire on a range of issues from the botched rollout of Obamacare to the Benghazi attacks, and now the VA scandal and the prisoner swap.
McCain has described the five Taliban figures just released from Guantanamo as "the hardest of the hard core."
He has said he is "eager to learn what precise steps are being taken to ensure that these vicious and violent Taliban extremists never return to fight against the United States."
The administration has said a condition of their release is that they will be sent to host country Qatar and required to remain there for one year and not reenter the fight in Afghanistan or elsewhere. But earlier detainees have been reported rejoining the fight and McCain's concerns are widely shared beyond his Republican Party.
Accordingly, the prisoner swap has joined the issues of Obamacare, the VA service to war veterans fiasco and the Benghazi debate as fodder for partisan rhetoric plaguing the president and is party throughout the approaching congressional election campaigns this fall, with John McCain tenaciously in the forefront.
Ever since his defeat at Obama's hands in his 2008 presidential bid, McCain has labored to regain stature in his party as a leading spokesman and shaper of opposition to the Obama foreign policy.
He has called for a more muscular posture against Russian President Vladimir Putin in his adventurism in Georgia and Ukraine, and for U.S. military aid to the insurgents in the civil war in Syria, hammering at Obama for toothless rhetoric toward the massive refugee plight.
Prior to McCain's failed presidential run, he reveled in the identity of a maverick in his party, at the cost of considerable internal support.
But now, in conspicuously manning the Republican and conservative barricades against Obama, who beat him at the ballot box nearly six years ago, John McCain remains in the forefront of the opposition fight to frustrate the rest of his second-term.
Editor's note: Jules Witcover's latest book is Joe Biden: A Life of Trial and Redemption" (William Morrow). You can respond to this column at firstname.lastname@example.org.