In his essay on President Obama’s first term, James Fallows dismisses Obama’s conceit that he would prefer to be “a really good one-term” president than a “mediocre” president who served two terms. “The reality,” Fallows writes, “is that our judgment about ‘really good’ and ‘mediocre’ presidents is colored by how long they serve. A failure to win reelection places a ‘one-term loser’ asterisk on even genuine accomplishments. Ask George H. W. Bush, victor in the Gulf War; ask Jimmy Carter, architect of the Camp David agreement.”

For Obama, it’s about more than the asterisk. The most important fact of Obama’s reelection campaign is that, if he wins, the single most important accomplishment of his second term would be protecting the gains of his first term. If he wins, the Affordable Care Act — barring a truly unexpected ruling from the Supreme Court — becomes the law of the land. If he wins, Dodd-Frank becomes the law on Wall Street. If he loses, both policies are likely to either be rolled back or hollowed out. Bush’s victory in the Gulf War withstood Bill Clinton’s election, and the Camp David agreement was not undone by Ronald Reagan. In Obama’s case, however, a failure to win a second term will not just color his accomplishments. It will decide their fate.

Moreover, if Obama wins a second term, his accomplishments would be comparatively limited. He would not enjoy anything like the congressional majorities of his first two years again. He is likely to face a Republican House or a Republican Senate or both. What he can accomplish in terms of new legislation will thus depend on how much congressional Republicans want him to accomplish, in terms of new legislation. Although there’s some reason to believe that losing the 2012 election could empower more moderate factions in the GOP, anything beyond modest levels of cooperation would remain unlikely. Divided government is not the place for miracles. As such, it’s likely to be the legislation from Obama’s first term that decides his legacy and holds the most hope of addressing the country’s toughest policy problems.

Of late, there have been a number of sweeping assessments of Obama’s first term. Andrew Sullivan’s essay in Newsweek was the most admiring. Obama, he writes, plays a “long game” that frustrates his supporters and detractors, alike, but has led to an incredible record of success on his core priorities. “The president begins by extending a hand to his opponents; when they respond by raising a fist, he demonstrates that they are the source of the problem; then, finally, he moves to his preferred position of moderate liberalism and fights for it without being effectively tarred as an ideologue or a divider.”

Noam Scheiber’s article on “Obama’s Worst Year” — which is an excerpt from his new book on Obama’s economic team, “The Escape Artists” — is more critical. He argues that “Obama’s greatest vulnerability as a leader” has been his consistent misunderstanding of the opposition, his endless desire to cut a deal with Republicans. To Scheiber, Obama’s turn toward deficit reduction in 2011 was an unmitigated disaster. “His initial approach was too passive and too accommodating, and he stuck with it far too long.” The saving grace was his eventual recognition that confrontation was necessary. This pattern of extended passivity followed by miraculous recovery, Scheiber says, has been present throughout Obama’s career: It was there in his primary campaign against Hillary Clinton, his response to Jeremiah Wright, his health-care plan. “Sooner or later, Obama may encounter a crisis that can’t be reversed at the eleventh hour,” Scheiber warns.

Fallows’s piece is perhaps the most balanced of the three. Obama “was unready for the presidency and temperamentally unsuited to it in many ways,” and yet, there has been a profound “underappreciation of his skills and accomplishments — an underappreciation that is as pronounced as the overestimation in those heady early days.” For Fallows, the best argument for Obama’s second term is that he has learned important lessons during his first. “The evidence suggests that given a second term, he would have a better chance of becoming the figure so many people imagined.”

All three pieces are smart, perceptive and worth reading in full. But they all suffer from the same flaw: They don’t convincingly consider the counterfactual.

Sullivan lists Obama’s accomplishments and documents the economy’s recovery, but he never asks, much less answers, the question of whether a different strategy or philosophy would have led to better legislation, a swifter recovery, or a less polarized atmosphere. His essay is an answer to Obama’s loudest and most superficial critics, but it is not, as such, a persuasive defense of Obama’s record against more nuanced objections.

Scheiber harshly criticizes the administration’s handling of the debt-ceiling negotiations, writing that “the proper response to such a threat is to refuse to negotiate under duress.”

But the Republicans had just won an election, and raising the debt ceiling was — and is — wildly unpopular. It is simple to imagine a world in which the administration refused to negotiate, only to see the debt ceiling breached, the economy fall into turmoil, and the White House stuck with the blame. Comparatively, the fact that Obama managed to persuade much of the country of what Scheiber and others consider to be the most salient fact of modern American politics — that the Republican Party has become so extreme that it would prefer Obama’s destruction to genuine compromise — can and should be seen as a major political accomplishment.

Fallows thinks Obama is personally aloof, emotionally cold, overly comfortable with an insular circle of advisers, and perhaps consequentially, has been unable to fully connect with the American people during a period of economic crisis or understand the implacable nature of his Republican opposition. But Clinton, Obama’s opposite in all matters emotional or rhetorical, achieved less in the way of legislation, struggled mightily with popular opinion, and lost the House to the Republicans for the first time in 40 years, despite a much stronger economy than Obama has enjoyed. Perhaps Clinton would have been better suited for this moment, and Obama better suited for the early ’90s. But the comparison does not immediately redound to the particular mixture of personal qualities that Clinton has and Obama lacked.

Of course, the presidency is not a lab experiment. We cannot tweak a few variables and rerun the past few years to test their effect. In that way, reviewing the flaws in a presidency is a hard thing to do well, and an impossible thing to do perfectly. Every political pundit — indeed, every citizen — has ideas about what could have been done better. But they have no way to know if their ideas really would have led to a better outcome, or simply to new, and perhaps even worse, problems. It is not Sullivan, Scheiber or Fallows’s fault that time only flows in one direction.

What we do know is what Obama has actually done. Health-care reform. Dodd-Frank. The stimulus bill. The 2010 tax deal. The stepped-up campaign of drone strikes in Afghanistan. The raid on Osama bin-Laden’s compound in Pakistan. The rejection of the Keystone XL pipeline. Solyndra. The appointments of Sonia Sotomayor and Elena Kagan. The continuation of the Bush administration’s expansive view of executive authority, particularly as it relates to the war on terror. The end of the Iraq war.

We also know what Obama wants to do. Raise taxes on the wealthy. Invest in infrastructure. Address climate change. Reduce the deficit, albeit on a more gradual path than many Republicans say they would prefer. Roll back Citizens United. End the war in Afghanistan. And, perhaps most importantly, entrench the major pieces of legislation passed in his first term.

It is very hard to say with any confidence what Obama could have done differently, and how it would have turned out. Another flaw in all these pieces — and in this article, and in almost all political punditry — is that the president is almost the sole focus, and the agency of other political actors and the importance of other institutions is almost entirely ignored. But there is no path Obama could have taken in the past year that does not rest on the question, “What would John Boehner/Mitch McConnell/Ben Bernanke/Susan Collins have done in response?” And yet vastly less energy is expended on the motivations and incentives of these players.

What we can do is say what Obama has done, and what he wants to do next. Given that Mitt Romney is running on a very different platform, and is backed by a very different coalition, the question is not whether Obama “deserves” a second term, or even whether he has learned anything in his first term that will substantially change his approach to governing in his second. It is whether Romney’s vision of the country is preferable to Obama’s. Because the truth of the matter is that the legislation Obama has already signed into law is far greater in scope and ambition than anything he has subsequently proposed, or is likely to pass. For Obama’s presidency to be remembered as one of the most consequential in recent American history, he does not need a new strategy, or a new personality. He simply needs to win a second term so that he can protect the accomplishments of his first.