If you’re a political junkie with Internet access looking for cheap laughs — and if you’re reading this column, you probably are — take a minute, go to YouTube and search for “Nixon” and “Rove.”

Your query will yield a 1972 CBS Nightly News segment on Richard M. Nixon’s reelection campaign. At the four-minute mark — not long after a passing mention of “an electric paper-shredding machine, to destroy secret campaign documents,” located “just out of sight” at Nixon headquarters — we meet the soft-cheeked, thick-sideburned 21-year-old Rove. Already the director of the College Republicans, Rove speaks with evident polish, touting the campaign’s youth outreach effort.

However amusing the interview with Rove (done by Dan Rather), the operative’s role in Nixon’s 1972 organization — the one that brought us Watergate — is more than a curiosity. Rove has recently found himself in legal peril again, this time alleged to have sought to politicize the non-partisan General Services Administration, along with scrutiny for his part in the firings of eight United States attorneys. The reminder of his roots in Nixon’s anything-to-win political machine is telling.

When George W. Bush became president, the smart money pegged him as Ronald Reagan redux. Bill Keller, now the executive editor of The New York Times, persuasively laid out the case in a nearly 8,000-word piece for the Sunday Magazine titled “Reagan’s Son.” The two men, he pointed out, had similar political agendas in cutting social services and taxes on the rich and projecting American military power abroad. They also shared a management style, establishing their administrations’ big picture while delegating details.

In his ideology and his policies, Bush’s debt to Reagan has been borne out. (Conservative purists back in the day even accused Reagan, as they do Bush now, of betraying their principles when he became unpopular.) In other ways, however — Bush’s political style, his attitudes toward executive power, and his contempt for democratic procedures — it has been clear for many years now that his real role model is Nixon.

The resemblances could fill a magazine article as long as Keller’s. Both Bush and Nixon, resentful of the supposed cultural dominance of liberals, perfected a conservative populism that vilifies academics, journalists, bureaucrats and other professionals as out-of-touch elites. Both men, hostile to the news media, rigidly prescribed the messages that their staffers could take to the press. Both vaunted secrecy, restricted access to information, and politicized areas of the government once deemed the province of non-partisan experts.

Iraq has generated even more echoes of the Nixon years. In a book review in The New York Times recently, Michiko Kakutani said it was hard to read Robert Dallek’s new tome, “Nixon and Kissinger” without regarding it “as a kind of parable about the presidency of George W. Bush and its determination to stay the course in Iraq.” Regardless of whether you agree that Iraq resembles Vietnam, Bush has certainly used the pretext of being a “war president” to justify curtailing civil liberties, expanding presidential power, and demonizing dissenters — as Nixon had. Claiming national security threats without furnishing the evidence to prove their claims, both men also illegally wiretapped Americans.

Interesting as the parallels are, however, the Nixon presidency matters to the Bush presidency less as an analogue than as history. Nixon’s was not simply a species of presidency similar to Bush’s but was the soil from which the Bush presidency grew. Rove’s dirty tricks matter, in other words, because they establish a direct lineage between the anything-goes mentality of the Nixon White House and the hardball of the Bush administration.

It’s been widely reported, for example, that Rove’s mentors in the College Republicans during the Nixon years included dirty-tricks maestros Lee Atwater and Donald Segretti. Newspapers have also reported that in 1970 Rove sneaked into the campaign headquarters of a Democratic candidate for state office in Illinois, filched campaign letterhead, and sent out fake fliers aiming to discredit the Democrat. In my own research on Nixon, I discovered that during Watergate itself, Rove used a phony grassroots organization to try to rally Americans to the president’s defense against what he called “the lynch-mob atmosphere created” by “the Nixon-hating media.” And according to Nixon’s former counsel John Dean, the Watergate prosecutor’s office took an interest in Rove’s underhanded activities before deciding “they had bigger fish to fry.”

Rove, moreover, is hardly the only link in the chain. Indeed, his youth outreach effort of 1972 had some success. A whole generation of conservative activists came of age in the 1970s either working for Nixon or, more commonly, voluntarily defending him on campuses and in political circles. His shame was their outrage.

These young conservative activists essentially endorsed the line that Nixon put out during Watergate— that “everybody does it.” They agreed that the president had to resign only because a double standard prevailed in the media and in Washington. Nixon’s dirty tricks, his efforts to politicize the civil service and discredit the media, and his willingness to use executive power for personal and political gain were really no cause for indignation. They were politics as usual.

“Frost/Nixon,” a new play about Nixon’s 1977 interviews with the British talk-show host David Frost, recently came to Broadway. Appropriately enough, it stars the former Dracula, Frank Langella, as Nixon. In the drama, as in the real-life interviews with Frost, Nixon’s most memorable line came when he said: “When the president does it, that means that it is not illegal.” Audiences roar at the comment. But they do so, I fear, only because they are hearing it spoken by a delightfully hammy Langella amid the opulence of a Broadway theater.