As Ron Paul took a major step toward launching his third presidential campaign Tuesday with the announcement of a presidential exploratory committee in Iowa, the political winds would appear to be more favorable than they were during his previous runs for the nation's highest office in 1988 and 2008.

Paul's warnings about the precariousness of the U.S. financial system seemed to have been vindicated by banking's near collapse and the subsequent Great Recession. And the rise of the tea party movement has fed off of the small-government philosophy and strict Constitutionalism that Paul has preached for decades. So Ron Paul is more than a Republican congressman from Texas, which is a good thing for him, because the last time a sitting House member was elected president of the United States was 1880.

Rep. Paul's biggest challenge in emerging as a viable candidate amid a conservative primary electorate is likely to be the same one that kept him confined to the single-digits at the polling booth during his 2008 run: his non-interventionist foreign policy philosophy.

All of the prospective Republican candidates have condemned President Obama's leadership on the international stage and have taken particular issue with the president over his handling of the U.S. military response in Libya. And while each of them has, at times, sounded similar notes to the ones that Paul has long trumpeted, their hands-off impulses apply only to Libya. For Paul, it goes much deeper.

"We can't afford any actions that don't take care of crucial U.S. needs and meet our own interests at this point," former Alaska Gov. Sarah Palin wrote in a Facebook post directed at Obama on Tuesday. "You are the Commander in Chief, so please explain what you believe is our ‘interest' there and not elsewhere."

That's the kind of thing Ron Paul has said for years. But while Palin and the other possible Republican White House hopefuls typically waste few opportunities to criticize Obama's foreign policy, they are far from kindred spirits with Paul in his calls to withdraw from international hotspots -- particularly Afghanistan, where U.S. troops are not scheduled to depart until 2014.

"The question we're facing today is should we leave Afghanistan?" Paul said on the House floor last month. "I think the answer is very clear, and it's not complicated, and of course we should -- as soon as we can. This suggests that we can leave by the end of the year."

With Haley Barbour now out of the race, former Arkansas Gov. Mike Huckabee is the only top-tier prospective GOP candidate to raise what he called "doubts" about the American endgame in that country, and with Huckabee's prospective candidacy remaining in limbo, it is not difficult to imagine a scenario in which the other candidates could gang up on Paul on a debate stage to dismiss his foreign policy views as extreme, in a repeat of what happened in 2008.