– The Republican Party may be turning anti-war.

Some of the shift is driven by visceral distrust of President Obama, who is proposing military strikes against Syria. Some is driven by remorse and the Iraq war. And some is fed by the isolationist and libertarian strains of the grass-roots Tea Party movement.

Plenty of Republicans, including key congressional leaders, support Obama's push for military action against the Syrian regime for allegedly using chemical weapons. But among constituents, rank-and-file members of Congress and many in the party's echo chamber, the trend is decidedly anti-war.

The party's popularity surged in the late 1940s partly because of its unrelenting stance against communism. Republicans nominated World War II hero Gen. Dwight D. Eisenhower as its 1952 presidential candidate and he won two terms. Ronald Reagan's presidency is still revered by supporters for his tough talk against the Soviet Union, and in his 2005 inaugural address, President George W. Bush redefined America's international mission.

Now, that's changing.

In 2002, just seven Republicans in Congress opposed giving Bush authorization to attack Iraq. Now, nearly 170 oppose or lean toward opposing Obama's request for authorization to strike Syria, according to news media tallies.

Some say politics driving opposition

Some analysts see anti-Obama sentiment driving the change of course.

"If this were a Republican president making the exact same case, more Republicans would be supportive," said Justin Logan, director of foreign policy studies at the libertarian Cato Institute.

Republicans said Obama does get a different reaction, but only because he's got a different track record on foreign policy and the military.

"I am all too aware that many Mississippians have zero desire to engage in another conflict in the Middle East," said Rep. Steven Palazzo, R-Miss., elected in 2010, when the Tea Party helped Republicans win control of the House.

That isolationist strain is proving increasingly popular. The Senate's potential 2016 Republican presidential candidates all are pushing non-intervention and finding appreciative audiences.

"When no compelling American interests exist, we should not intervene. No compelling interests exist in Syria," said Sen. Rand Paul, R-Ky. His father, Ron, then a Texas congressman, was one of six House Republicans to vote against the Iraq war in 2002. Sens. Ted Cruz, R-Texas, and Marco Rubio, R-Fla., also plan to oppose the current effort to strike Syria.