WASHINGTON -- Bill Clinton's greatest domestic achievement, aside from abolishing welfare, was free trade. The crown jewel was the North American Free Trade Agreement. He got that through Congress over sustained union opposition in 1993. Monday, Sen. Hillary Clinton proposed that NAFTA and other existing trade agreements be reassessed every five years.

The Washington Post correctly calls Hillary's retreat from free trade "opportunism under pressure," the pressure being the rampant and popular protectionism of her presidential rivals, particularly in protectionist Iowa. But while "opportunism under pressure" suggests (pace Hemingway) cowardice, the better description of Clintonism is slipperiness. Adaptability. Cynicism, if you like.

Note her clever use of terms. Reassessing NAFTA sounds great to protectionists, but it is perfectly ambiguous. It could mean abolition or radical curtailment. It could also mean establishing a study commission whose recommendations might not reach President Hillary Clinton's desk until too late in her second term.

The Post editorial noted "a perverse kind of good news" in Hillary's free-trade revisionism: "There's little chance that her position reflects any deeply held principle." And there lies the beauty not just of Clinton on free trade but of the Clinton candidacy itself: She has no principles. Her liberalism is redeemed by her ambition; her ideology subordinate to her political needs.

I could never vote for her, but I (and others of my ideological ilk) could live with her -- precisely because she is so liberated from principle. Her liberalism, like her husband's -- flexible, disciplined, calculated, triangulated -- always leaves open the possibility that she would do the right thing for the blessedly wrong (i.e. self-interested, ambition-serving, politically expedient) reason.

I could never vote for her because the Clintons' liberal internationalism on display in the 1990s -- the pursuit of paper treaties and the reliance on international institutions -- is naive in theory and feckless in practice. And her domestic policy sees state intervention and expansion as the answer to every human ill from mortgage default to the common cold. Nonetheless, if 2008 is going to be a Democratic year, as it very well could, Hillary would serve the country better than any of her Democratic rivals.

On Iraq, for example, she talks like someone who knows she may soon be commander in chief and will need room to maneuver in order to achieve whatever success might be possible. Clinton has emphatically refused to give assurances that she would get us out of Iraq during her first term. Unlike, for example, Bill Richardson, who advocates a rout so radical that we'd leave equipment behind, she has committed herself to little more than a drawdown of forces as conditions allow.

On Iran, Clinton has been pilloried from the left for supporting a completely anodyne resolution designating Iran's Revolutionary Guard Corps as a terrorist organization. This would trigger serious economic sanctions that would greatly complicate its ability to operate.

Her leading rivals opposed the resolution on the bogus grounds that it is a blank check for Bush to go to war with Iran. It is nothing of the sort. An earlier version of the Iran resolution that would have allowed "the prudent and calibrated use of all instruments" to counter Iranian activity inside Iraq might indeed have been interpreted as such an authorization. But that provision was dropped in the resolution that Clinton, and 75 other senators, voted for.

And look what Clinton unveiled this week: a modestly government-subsidized, personal retirement account. True, it is yet another big-government middle-class entitlement. Yes, she ignores the looming Social Security crisis. On the other hand, establishing a universal, portable, personal retirement account (though without the government subsidy) is something conservatives have long and devoutly sought. It establishes a parallel to the Social Security system -- the perfect vehicle for a future conservative administration to use for shifting from the current unsustainable government-controlled program to a privatized system such as the one in Chile.

Even Clinton's response to a debate question on torture -- "As a matter of policy it cannot be American policy, period" -- is elegantly phrased to imply an implacable opposition to torture, and yet leave open the possibility that in extreme circumstances a president would do what she had to do, i.e. authorize torture, regardless of the express policy.

Clinton rarely falters. Always careful, always calibrated, always leaving room for expediency over ideology. That's Clintonism, of both marital flavors. Gender sensitivity prevents me from calling her the consummate needle-threader. Consider her instead Columbus' match as the Great Navigator.