(CNN) -

Sen. Rand Paul of Kentucky is firing back at Gov. Rick Perry of Texas, in an escalation of a war of words between two potential 2016 Republican presidential contenders over U.S. foreign policy and the country's role in the bloody outbreak of fighting in Iraq.

"There are many things I like about Texas Gov. Rick Perry, including his stance on the Tenth Amendment to the Constitution. But apparently his new glasses haven't altered his perception of the world, or allowed him to see it any more clearly," Paul wrote in an op-ed that appeared Monday in Politico, taking aim at the much talked about eye-wear Perry's been sporting since last year.

"There are obviously many important events going on in the world right now, but with 60,000 foreign children streaming across the Texas border, I am surprised Governor Perry has apparently still found time to mischaracterize and attack my foreign policy," added the first-term senator who doesn't want the U.S. to be the world's policeman.

Paul's critics, such as Perry, liken it to outright isolationism.

"Curiously blind" and "wrong" is how Perry described Paul's foreign policy, in an op-ed Friday in the Washington Post.

"Governor Perry writes a fictionalized account of my foreign policy so mischaracterizing my views that I wonder if he's even really read any of my policy papers," Paul fired back on Monday.

Perry criticizes Paul

This latest skirmish between the two men started with Perry's Washington Post op-ed.

"As a veteran, and as a governor who has supported Texas National Guard deployments to Iraq and Afghanistan, I can understand the emotions behind isolationism. Many people are tired of war, and the urge to pull back is a natural, human reaction," Perry wrote. "Unfortunately, we live in a world where isolationist policies would only endanger our national security even further."

"That's why it's disheartening to hear fellow Republicans, such as Sen. Rand Paul (Ky.), suggest that our nation should ignore what's happening in Iraq."

Three weeks ago, during an interview with CNN Chief Political Correspondent Candy Crowley, Paul said: "I'm not willing to send my son into that mess."

"Let's not be involved in the Iraq civil war," Paul said, referring to weeks of violence across that country. Radical Sunni militants have battled Prime Minister Nuri al-Maliki's Shiite government forces. The Islamic State in Iraq and Syria, or ISIS, has not only gained ground in northern and western Iraq but also in Syria.

Perry took Paul's sentiments to task.

Noting "the main problem with this argument is that it means ignoring the profound threat that the group now calling itself the Islamic State poses to the United States and the world," the governor wrote. ". ...This represents a real threat to our national security --- to which Paul seems curiously blind --- because any of these passport carriers can simply buy a plane ticket and show up in the United States without even a visa."

Perry then picked apart an opinion piece Paul recently wrote in the Wall Street Journal arguing against U.S. military intervention in Iraq.

Perry wrote that Paul went "so far as to claim...that President Ronald Reagan's own doctrines would lead him to same conclusion," adding that , "his analysis is wrong. Paul conveniently omitted Reagan's long internationalist record of leading the world with moral and strategic clarity."

And in perhaps one of his harshest critiques, Perry lumped Paul together with a favored political enemy of conservatives: President Barack Obama.

"Viewed together, Obama's policies have certainly led us to this dangerous point in Iraq and Syria, but Paul's brand of isolationism (or whatever term he prefers) would compound the threat of terrorism even further," Perry wrote.

The longtime Texas governor is not running for re-election this year. Instead, recent moves and a higher public profile by Perry appear to be indicators that he will make a second run for the GOP presidential nomination. Perry's 2012 bid started strong, but thanks to a number of well publicized stumbles, his campaign crashed and burned.

Paul fires back

Paul responded to that in his op-ed Monday, writing, "some of Perry's solutions for the current chaos in Iraq aren't much different from what I've proposed, something he fails to mention. His solutions also aren't much different from President Barack Obama's, something he also fails to mention. Because interestingly enough, there aren't that many good choices right now in dealing with this situation in Iraq."

And Paul wrote that Perry, along with many other Republicans, have misread Reagan's "peace through strength" doctrine.

"Strength does not always mean war. Reagan ended the Cold War without going to war with Russia. He achieved a relative peace with the Soviet Union-the greatest existential threat to the United States in our history-through strong diplomacy and moral leadership," Paul wrote.

"Reagan had no easy options either. But he did the best he could with the hand he was dealt. Some of Reagan's Republican champions today praise his rhetoric but forget his actions. Reagan was stern, but he wasn't stupid. Reagan hated war, particularly the specter of nuclear war. Unlike his more hawkish critics-and there were many-Reagan was always thoughtful and cautious."

Paul, the son of three-time presidential candidate and former Texas Rep. Ron Paul, is considered one of the frontrunners right now among the potential 2016 GOP White House hopefuls. While he's popular among many in the party's base, he also appears to enjoy some support from younger voters as he tries increase Republican Party outreach to groups that historically favor the Democratic Party.