President Obama's yearning to become a peacetime president continues to be frustrated by the reality on the ground in the Middle East, and by Republicans' zeal to capitalize on it politically at home.

The disintegration of Iraq, the emergence of a new extremist "Islamic State," a deepening of the Israeli-Palestinian stalemate and more Russian mischief in Ukraine all have combined to challenge the Obama Doctrine of selective use of power in foreign policy.

As the Middle East crumbles, the GOP'swould-be 2016 presidential hopefuls have commenced kibitzing. They have paid particular interest not only to Mr. Obama but also to Kentucky Sen. Rand Paul, whom they have branded an isolationist in hopes of countering his early grasp of the media spotlight.

Texas Gov. Rick Perry, whose 2012 bid for the Republican presidential nomination fizzled out with an embarrassing memory lapse on federal agencies he would eliminate, appears to be retooling for a second try, this time as a foreign policy expert. He reintroduced himself to the national political audience last weekend with an article in the Washington Post headlined "Why Rand Paul is wrong about Iraq."

Mr. Paul had written last month in the Wall Street Journal that the United States should return to the foreign policy of Ronald Reagan. He cited a speech by former Secretary of Defense Casper Weinberger saying the United States should not commit forces in combat unless its vital national interests and those of its allies are involved, and only "as a last resort."

One could argue that this view also defines the Obama Doctrine. But, Mr. Perry wrote, "Paul conveniently omitted Reagan's long internationalist record of leading the world with moral and strategic clarity. Unlike the noninterventionists of today, Reagan believed that our security and economic prosperity require persistent engagement and leadership abroad. He, like Eisenhower before him, refused to heed 'the false prophets of living alone.' "

Thus did Mr. Perry, a man with little on his resume to link himself with two latter-day icons on foreign policy, take on the early leader in the 2016 Republican presidential speculation. The Texas governor joined strong interventionists Sen. John McCain, former Speaker Newt Gingrich and former Vice President Dick Cheney in taking Mr. Paul to task. Mr. McCain accused him of advocating a withdrawal "to fortress America," and Cheney in a Politico interview said anyone "who thinks after 9/11 we can retreat behind the safety of two oceans" is "out of touch."

This early ganging up on Paul is little more than intramural sport at this stage. But it also signals the GOP's intensifying focus on Obama's seemingly temperate response to the growing threat of new terrorism from the emerging Islamic state of Iraq and Syria(ISIS). In his Post op-ed, Mr. Perry pivoted from Mr. Paul to Mr. Obama in what will be a familiar Republican chorus in the run-up to this fall's midterm congressional elections.

"In the face of the advancement of the Islamic state, Mr. Paul and others suggest the best approach to this 21st century threat is to do nothing," Mr. Perry wrote. "I personally don't believe in a wait-and-see foreign policy for the United States. Neither would Reagan.

"Reagan led proudly from the front, not from behind, and when he drew a 'red line,' the world knew exactly what he meant. Paul is drawing his own red line along the water's edge, creating a giant moat where superpowers can retire from the world."

Including Mr. Obama in his indictment, Mr. Perry said of the president's red lines that "the world knows by now that this is a rhetorical device or negotiating ploy rather than a promise of action." This has enabled al-Qaida "to regroup." Mr. Obama's policies, Mr. Perry concluded, "have certainly led us to this dangerous point in Iraqand Syria, but Paul's brand of isolationism ... would compound the threat of terrorism even further."

Mr. Perry may be a neophyte in foreign policy, but politically he has demonstrated a capability for hitting two birds with one stone, in linking Mr. Paul and Mr. Obama as brothers in isolationism. Not a bad re-entry into the political fray he left so ignominiously in 2012. 

Jules Witcover is a syndicated columnist and former long-time writer for The Baltimore Sun. His latest book is "Joe Biden: A Life of Trial and Redemption" (William Morrow). His email is juleswitcover@comcast.net.