“This is isolationism,” McCain said of the opposition to the U.S. Libya mission from congressional Republicans and GOP presidential candidates. “There’s always been an isolationist strain in the Republican Party, the Pat Buchanan wing of our party. But now it seems to have moved more center stage, so to speak.”

McCain isn’t alone. Two days later, Minnesota Gov. Tim Pawlenty (R), one of the presidential contenders McCain had chastised, said in an interview with Politico that now he’s concerned the Republican Party is drifting toward an isolationist view.

“I don’t like the drift of the Republican Party toward what appears to be a retreat or a move more towards isolationism,” Pawlenty said.

So, is the Republican Party – which has in recent years been home to more hawks than doves -- actually taking a turn toward isolationism?

Not exactly. Despite recent support by Republicans for ending, or at least more fully explaining, the war in Libya, a look at support for the Afghanistan conflict suggests that the Republicans as a whole haven’t molted into doves after all.

The distinction is important as President Obama prepared to make a major speech on the Afghanistan conflict Wednesday night, which was expected to call for withdrawing all U.S. troops by the end of 2012.

House Speaker John Boehner (R-Ohio) on Wednesday argued that if there’s any war weariness among House Republicans on Afghanistan, it’s a reflection of the sentiments of the American public at large.

“Members of Congress on both sides of the aisle reflect the opinions and attitudes of their constituents, and the American people are a bit weary about Afghanistan, and you can’t blame them,” Boehner said. “You’ve got 100,000 of our men and women fighting in the desert over there.”

Boehner added that he’s “concerned about any precipitous withdrawal” of troops “that would jeopardize the success that we’ve made,” explaining that he would support any Obama drawdown plan as long as the president bases his decision on the advice of military and diplomatic officials on the ground.

Senate Minority Leader Mitch McConnell (R-Ky.) said that Republicans might simply feel freer to disagree with the foreign policy of a Democrat in the White House.

“ I do think there is more of a tendency to pull together when the guy in the White House is on your side,” McConnell told reporters Wednesday morning. “I think a lot of our members, not having a Republican in the White House, feel more free to express their reservations.”

The recent debates over the U.S. military involvement in Libya and the drawdown of U.S. troops in Afghanistan have blurred party lines, to be sure.

Earlier this month, as the House debated a resolution from Rep. Dennis Kucinich (D-Ohio) that would have immediately ended the U.S. involvement in Libya and a separate measure from House Speaker John Boehner (R-Ohio) calling for the White House to further explain the mission, members from opposite sides of the aisle found themselves strangely united.

Boehner’s resolution would have passed the House with Republican support alone. It garnered the backing of all but ten Republicans and was even supported by 45 Democrats, for a final vote of passage, 268 to 145.

The Kucinich measure to end the war failed on a 148-to-265 vote. But it did, interestingly, pick up the support of more Republicans than Democrats: 87 Republican members -- about 36 percent of the House GOP conference -- backed it while it was supported by only 61 Democrats – 32 percent of the House Democratic Caucus.

Some might point tp those votes, as well as some of the more vocal calls by Republican members to halt the U.S. involvement in Libya, as signs that Republicans are becoming doves when it comes to Libya, at least.

But when it comes to Afghanistan, congressional Republicans are actually largely staying the course on foreign policy.

In early May, a bipartisan group of eight House members sent a letter to Obama calling for the removal of most U.S. forces from Afghanistan in the wake of Osama bin Laden’s killing.

But those eight had already been vocally opposed to the war and were among the 93 House members voting in mid-March to withdraw U.S. troops from Afghanistan as quickly as possible. (231 House members opposed the ultimately unsuccessful measure.)

Bin Laden’s death hadn’t brought about a significant shift within the Republican Party; rather, many of the same lawmakers on the right and left who had been urging for an immediate end to the U.S. war in Afghanistan seized on the successful bin Laden raid to further make their case.

Moreover, when the House voted in late May on an amendment sponsored by Rep. Jim McGovern (D-Mass.) that would have called on Obama to present “a plan and timeframe on negotiations leading to a political solution and reconciliation in Afghanistan,” only 26 Republicans – and no members of House GOP leadership -- joined all but eight Democrats in backing the measure. (The amendment failed on a 204-to-215 vote.)

Those 26 Republicans were more than the eight who voted for Kucinich’s immediate withdrawal in March, and greater than the five who backed a similar Kucinich measure last year. But it’s worth remembering that the small group amounts to just over 10 percent of the House Republican Conference.

If there appears to be a new “isolationist” strain within the Republican Party then it’s likely the result of lawmakers of questions surrounding the constitutionality of the Libyan intervention rather than any broader philosophical shift within the GOP. Lawmakers from both parties have criticized Obama for not abiding by the War Powers Act and seeking authorization from Congess for the Libyan action.

“There’s actually three things here: there’s funding, there’s the anti-war crowd, and then there’s the people in my camp, which is the constitutional, legal (camp),” said Rep. Tom Rooney (R-Fla.), who was among the 87 lawmakers who backed the Kucinich amendment.

Rooney planned to introduce his own amendment calling for troops to be withdrawn from Libya if Obama didn’t obtain congressional approval by June 19.

Rooney said that he believes there has been a shift among the House Republicans over the last several years, but that the shift has been to “make sure that something is in our national interest or in the interests of our allies” before the U.S. should take military action.

“I think that’s what the founders wanted, too; that’s why they put the declaration of war in our camp. ... I think that you’re seeing our conference getting to the point where we damn well better be sure what we’re doing before we just do it,” he said. “And I think that that’s healthy.”

Some Democrats sounded a similar note to McConnell, arguing that politics may figure larger in some members’ minds than the issue of the U.S. military involvement itself.

“On my side, I regret not being on the same side as my president,” said Rep. Michael Capuano (Mass.), one of the Democrats who has strongly criticized Obama on Libya. “I’m not happy about it, but party affiliation is second to the Constitution. It’s hard to tell on the Republican side. Some people might enjoy putting the president’s position to twist in the wind, I don’t know.”

Capuano pointed to a recent statement by McCain in which the Arizona Republican asked his colleagues how they would act on Libya if a Republican were in the White House.

“You should be voting on the basis of whether you think the military action is appropriate or not. Anyone who votes any other way, as far as I’m concerned, has a special place in hell for them,” Capuano said. “I don’t know that anybody does it, but anybody who does, that’s inappropriate.”

As the House takes up two Libya resolutions Thursday, politics will likely again be on display. One of the resolutions uses wording similar to the bipartisan measure advanced by Sens. McCain and Sen. John Kerry (D-Mass.) authorizing the limited use of force in Libya for one year, while the other resolution would remove U.S. forces from Libya except for those engaged in “non-hostile actions.” The latter measure is an apparent response to House frustrations over Obama’s argument that the Libyan conflict does not amount to “hostilities.”