There is no question that Barack Obama is one of our most enigmatic presidents. Despite having published two volumes of memoirs before being elected president, we really don’t know that much about what makes him tick. The ongoing debate over the deficit and the debt limit is clarifying what I think he is: a Democratic Richard Nixon.

To explain what I mean, I first have to tell some history.

Democrat Franklin D. Roosevelt was a transformative president, partly because of his policies but mainly because he presided over the two most disruptive events of the 20th century: the Great Depression and World War II.

By the time Dwight Eisenhower took office, people craved stability and he was determined to give it to them. This angered his fellow Republicans, who wanted nothing more than to repeal Roosevelt’s New Deal, root and branch. And with control of both the House and Senate in 1953 and 1954, he could have undone a lot of it if he wanted to.

But Eisenhower not only refused to repeal the New Deal, he wouldn’t even let Republicans in Congress cut taxes even though the high World War II and Korean War rates were in effect. He thought a balanced budget should take priority. Eisenhower also helped to destroy right wing hero Joe McCarthy and worked closely with liberals on civil rights.

Eisenhower’s effective liberalism was deeply frustrating to conservatives. Robert Welch of the John Birch Society even accused him of being a communist. But after Republicans lost control of Congress in 1954, he was the only game in town for them.

By 1964, conservatives got control of the GOP’s nominating process and put forward one of their own, Barry Goldwater, to complete the unfinished work of repealing the New Deal that Eisenhower refused to do. But he lost in a landslide to Lyndon Johnson, who quickly capitalized on his victory by doubling down on the New Deal with the Great Society.

Although Johnson was done in by Vietnam, his domestic liberalism was as popular in 1968 as the New Deal had been in 1952. Nevertheless, conservatives deluded themselves that Nixon would repeal the Great Society. But just as Eisenhower cemented the New Deal in place, Nixon accepted the legitimacy of the Great Society. His goal was to make it work efficiently and shave off the rough edges. Nixon even expanded the welfare state by expanding its regulatory reach through the Environmental Protection Agency and other new government agencies.

Conservatives were infuriated by Nixon’s betrayal, but lacking control of Congress they were stuck with him just as they had been with Eisenhower. Not very many were upset when Watergate pushed Nixon out of office.

Conservatives finally got the president they had always hoped for when Ronald Reagan was elected in 1980. But by then, key New Deal/Great Society programs like Social Security and Medicare were so deeply embedded in government and society that he never lifted a finger to dismantle them. Reagan even raised taxes 11 times to keep them funded.

Liberals initially viewed Bill Clinton the same way conservatives viewed Eisenhower – as a liberator who would reverse the awful policies of his two predecessors. But almost immediately, Clinton decided that deficit reduction would be the first order of business in his administration. His promised middle class tax cut and economic stimulus were abandoned.

By 1995, Clinton was working with Republicans to dismantle welfare. In 1997, he supported a cut in the capital gains tax. As the benefits of his 1993 deficit reduction package took effect, budget deficits disappeared and we had the first significant surpluses in memory. Yet Clinton steadfastly refused to spend any of the flood of revenues coming into the Treasury, hording them like a latter day Midas. In the end, his administration was even more conservative than Eisenhower’s on fiscal policy.

And just as pent-up liberal aspirations exploded in the 1960s with spending for every pet project green lighted, so too the fiscal conservatism of the Clinton years led to an explosion of tax cuts under George W. Bush, who supported every one that came down the pike. The result was the same as it was with Johnson: massive federal deficits and a tanking economy.

Thus Obama took office under roughly the same political and economic circumstances that Nixon did in 1968 except in a mirror opposite way. Instead of being forced to manage a slew of new liberal spending programs, as Nixon did, Obama had to cope with a revenue structure that had been decimated by Republicans.

Liberals hoped that Obama would overturn conservative policies and launch a new era of government activism. Although Republicans routinely accuse him of being a socialist, an honest examination of his presidency must conclude that he has in fact been moderately conservative to exactly the same degree that Nixon was moderately liberal.

Here are a few examples of Obama's effective conservatism:

His stimulus bill was half the size that his advisers thought necessary;

He continued Bush’s war and national security policies without change and even retained Bush’s defense secretary;

He put forward a health plan almost identical to those that had been supported by Republicans such as Mitt Romney in the recent past, pointedly rejecting the single-payer option favored by liberals;

He caved to conservative demands that the Bush tax cuts be extended without getting any quid pro quo whatsoever;

And in the past few weeks he has supported deficit reductions that go far beyond those offered by Republicans.

Further evidence can be found in the writings of outspoken liberals such as New York Times columnist Paul Krugman, who has condemned Obama’s conservatism ever since he took office

Conservatives will, of course, scoff at the idea of Obama being any sort of conservative, just as liberals scoffed at Nixon being any kind of liberal. But with the benefit of historical hindsight, it’s now obvious that Nixon was indeed a moderate liberal in practice. And with the passage of time, it’s increasingly obvious that Clinton was essentially an Eisenhower Republican. It may take 20 years before Obama’s basic conservatism is widely accepted as well, but it’s a fact.