In 1950, President Harry S. Truman was under fire for "losing" China to communist forces, engaging in deficit spending and seeking to expand unemployment insurance. Harold E. Stassen, a prominent Republican, blasted him as "the worst president ever to occupy the White House."

Four years later, under Dwight D. Eisenhower, job growth had slowed and wages were down. West Virginia Sen. Matthew M. Neely declared Ike "the worst president in United States history."

In 1973, as Richard M. Nixon foundered amid the worsening Watergate scandal, crippling stagflation and increasing social strife, labor leader George Meany asserted, "He will go down in history as one of our worst presidents."

Six years into Ronald Reagan's presidency, the Iran-contra scandal broke and his approval ratings fell into the 40s. Ted Sorensen, who was a speechwriter for John F. Kennedy, suggested that Reagan could well be remembered "as one of our worst presidents."

Considering these moments from history, how likely is it that George W. Bush, as many now assert, is our all-time worst president? Yes, many of us can easily tick off our own lists of Bush policies that we believe have done the United States significant harm. But any declarations that history will consign him to the bottom tier of presidents are premature. As the now-flourishing reputations of Truman, Eisenhower and Reagan attest, the antipathy a president elicits from his contemporaries usually fades over time.

And as Nixon's still-dismal reputation also attests, in the contest for the dubious title of "worst president," Bush faces stiff competition.

Comparisons of presidents across different eras are typically the stuff of parlor games, not serious historical study. But if anyone can be said to deserve the mantle of the worst, it's Nixon. Indeed, looking at his disastrous presidency may help put Bush's failures in perspective.

Like Bush, Nixon fancied himself a "wartime" president in the manner of Franklin D. Roosevelt and therefore entitled to deference in the face of a national emergency -- a view at odds with how most Americans see these controversial, far-off conflicts. And while the oft-cited analogies between the Vietnam and Iraq wars tend to be glib, each conflict has significantly determined its president's reputation. Like Nixon, Bush has heeded Henry Kissinger's advice not to withdraw from a quagmire, preferring to brand critics cowards or traitors. Like Nixon, Bush has also sought to conceal from the public the full scope of the U.S. commitment. Under blanket assertions of "national security" meant to end public debate, he has used Nixonian wiretapping to achieve his ends. These decisions will surely stain his legacy.

But can we conclude that Bush's war policy is worse than Nixon's? However toxic the fallout from Iraq, it's hard to imagine that it could greatly exceed the damage wrought by Vietnam, the wounds from which are still raw 30 years later, as its role in the 2004 presidential election showed. (On the other hand, Nixon can't be blamed for starting his war, whereas Bush initiated his -- albeit with substantial backing from Democrats.) Bush's view of power and his iron-fisted manner of governance also come from the Nixon playbook. Karl Rove, who headed the College Republicans during Watergate, sought to complete Nixon's mission of building a permanent Republican majority. In Nixonian fashion, the Bush-Rove strategy has been to use bullying to stifle opposition: demonizing the news media, discrediting policy experts, disdaining the separation of powers. Bush's theory of a "unitary" executive power is little more than a restatement of a Nixon utterance: "When the president does it, that means that it is not illegal."

But again, if Bush has given Nixon good chase when it comes to undemocratic hardball politics, he hasn't surpassed the master. Nixon's belief in the inherent legality of his own actions led him to authorize burglaries and approve criminal acts -- paying hush money, trying to get the CIA to lie to the FBI -- to thwart the Watergate investigation. And these were only the most well-known and well-documented of the counts against him in the articles of impeachment approved by the House Judiciary Committee in 1974.

While Nixon had his diehard defenders, something close to a national consensus emerged over the idea that his crimes were unprecedented and required his removal from office. Barry Goldwater conservatives and Lowell Weicker Republicans, libertarians and liberals, Main Streeters and Wall Streeters all agreed that Nixon was, if not necessarily the worst president in U.S. history, deserving of the most extreme reprimand ever visited on a commander in chief. Instead of being impeached and removed from office, Nixon resigned.

No such consensus exists for a Bush impeachment. On the contrary, in this fall's election campaign, Democrats pointedly quashed any talk of seeking his ouster if they were to win control of Congress. One can argue that Bush's sanctioning of illegal wiretapping by the National Security Agency constitutes an impeachable offense. His policy of depriving suspected terrorists and POWs of Geneva Convention protections may also strike some people as grounds for removal -- although Congress, by acquiescing in Bush's military detention policy last fall, made the latter argument a tougher sell.

Either way, judgments about the impeachability of Bush for such offenses are far less clear than those rendered in 1974 about Nixon's law-breaking. Many presidents skirt the edges of unconstitutionality. Only Nixon transgressed it so blatantly that impeachment became, to use a Bush-era phrase, a slam dunk.

Bush has two years left in his presidency and we don't know what they'll hold. They may be as dismal as the first six. Future investigations may bear out many people's worst fears about this administration's violations of civil liberties. And it's conceivable that the consequences of the invasion of Iraq may prove more destructive than those of Nixon's stubborn continuation of the Vietnam War. Should those things happen, Bush will be able to lay a claim to the mantle of U.S. history's worst president. For now, though, I'm sticking with Dick.

David Greenberg teaches history and media studies at Rutgers University.

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