Editor's note: Julian E. Zelizer is a professor of history and public affairs at Princeton University's Woodrow Wilson School. His new book, "Arsenal of Democracy: The Politics of National Security -- From World War II to the War on Terrorism," will be published this fall by Basic Books. Zelizer writes widely on current events.

Julian Zelizer says Republicans talk small government in theory but don't practice it in power.

PRINCETON, New Jersey (CNN) -- As the budget debate heats up, Republicans are warning of socialism in the White House and claiming that Democrats are rushing back to their dangerous tonic of big government.

Speaking to the Conservative Political Action Conference, Rush Limbaugh warned that "the future is not Big Government. Self-serving politicians. Powerful bureaucrats. This has been tried, tested throughout history. The result has always been disaster."

On CNN, former Vice President Dick Cheney said he is worried that the administration is using the current economic conditions to "justify" a "massive expansion" in the government.

After the past eight years in American politics, it is impossible to reconcile current promises by conservatives for small government with the historical record of President Bush's administration. Most experts on the left and right can find one issue upon which to agree: The federal government expanded significantly after 2001 when George W. Bush was in the White House.

The growth did not just take place with national security spending but with domestic programs as well. Even as the administration fought to reduce the cost of certain programs by preventing cost-of-living increases in benefits, in many other areas of policy -- such as Medicare prescription drug benefits, federal education standards and agricultural subsidies -- the federal government expanded by leaps and bounds. And then there are the costs of Afghanistan and Iraq.

Federal spending stood at about $1.9 trillion in 2000, when Democrat Bill Clinton ended his presidency. In his final year in office, Bush proposed to spend $3.1 trillion for fiscal year 2009. President Obama's budget proposal for fiscal 2010 is $3.6 trillion.

Nor can Republicans blame a Democratic Congress for being responsible for these trends. Much of the expansion took place between 2002 and 2006, when Republicans controlled both Congress and the White House. The Weekly Standard's Fred Barnes was writing about "big government conservatism" back in 2003.

Two years later, the right-wing CATO Institute published a report noting that total government spending had grown by 33 percent in President Bush's first term, lamenting that "President Bush has presided over the largest overall increase in inflation-adjusted federal spending since Lyndon B. Johnson."

There were some areas where Bush backed off government cuts because programs were too popular, like Social Security. In other areas, like federal education policy and prescription drug benefits, the president seemed enthusiastic about bigger government.

Bush and Cheney also embraced a vision of presidential power that revolved around a largely unregulated and centralized executive branch with massive authority over the citizenry. This was a far cry from the days of Ohio Sen. Robert Taft, a Republican who constantly warned about the dangers of presidential power to America's liberties.

After the 2008 election, Cheney was not apologetic. He explained that "the president believes, I believe very deeply, in a strong executive, and I think that's essential in this day and age. And I think the Obama administration is not likely to cede that authority back to the Congress. I think they'll find that given a challenge they face, they'll need all the authority they can muster."

Importantly, the marriage between conservatism and a robust federal government was not unique to the Bush presidency. The roots of Bush's comfort with government can be traced to the Republican Right in the 1950s, members of Congress who called for an aggressive response to domestic and international communism.

Presidents Dwight Eisenhower and Richard Nixon were two Republicans who pragmatically accepted that Americans had come to expect that the federal government would protect against certain risks and that trying to reverse politics to the pre-New Deal period would be politically suicidal.

"Should any political party," Eisenhower said, "attempt to abolish Social Security, unemployment insurance, and eliminate labor laws and farm programs, you would not hear of that party again in our political history."

When Nixon and congressional Republicans battled with Democrats over Social Security between 1970 and 1972, the debate revolved over how much to expand the program. Congressional Democrats wanted to increase benefits through the legislative process, while Nixon wanted to index benefits so they automatically increased with inflation.

Nixon and Congress did both.

President Reagan backed off his most ambitious efforts to cut government, most dramatically when he abandoned his proposal to curtail Social Security after facing a fierce backlash, while the military budget boomed. President George H.W. Bush signed the Americans with Disabilities Act in 1990, which was one of the boldest regulatory expansions of government since the civil rights laws of the 1960s.

All of these presidents, particularly Nixon and Reagan, likewise promoted a muscular vision of presidential power that strengthened the authority of government and introduced concepts, such as the unitary executive, which would become the intellectual underpinning of the Bush administration.

"When the president does it, that means that it is not illegal," Nixon told David Frost in 1977. Like it or not, strengthening the presidency is one of the most important ways in which the role of government has grown since the nation's founding.

Fifty years of American history have shown that even the party that traditionally advocates small government on the campaign trail opts for big government when it gets into power. The rhetoric of small government has helped Republicans attract some support in the past, but it is hard to take such rhetoric seriously given the historical record -- and it is a now a question whether this rhetoric is even appealing since many Americans want government to help them cope with the current crisis.

The opinions expressed in this commentary are solely those of Julian Zelizer.

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