As the 2012 Republican National Convention gathers in Tampa, I find my thoughts going back nearly half a century, to San Francisco in 1964. It was the first political convention I covered as a reporter, and it was the one at which Sen. Barry Goldwater of Arizona was nominated for president.

Then, as now, the air was filled with far-right conservative demands for restraints in the size and reach of government, capsulated in Goldwater's rousing call to the delegates: "I would remind you that extremism in the defense of liberty is no vice. And let me remind you also that moderation in the pursuit of justice is no virtue."

The Goldwater-dominated convention, mirrored today in the tea-party elements that have found a home in the Republican Party, erupted approvingly in a spasm of revulsion toward its lingering dissenters. Goldwater's chief challenger that year, liberal Gov. Nelson Rockefeller of New York, was roundly hooted as he tried to address the convention.

The reigning Republican hero of the day, President Dwight D. Eisenhower, visibly registered shock at the explosion of hate that flowed through the packed Cow Palace on the shores of the Pacific just south of the city. Goldwater punctuated the mood by choosing little-known but conspicuously partisan Congressman William E. Miller of upstate New York as his running mate because, he explained, "he drives Lyndon Johnson [the Democratic nominee] nuts."

To the surprise of few, Goldwater and Miller were trounced in November by the ticket of LBJ and Hubert Humphrey. But the Goldwater dream lived on in other Republican hearts, including that of Ronald Reagan. In a rousing speech endorsing Goldwater later in the campaign, he found what proved to be the launching pad for his own political climb to the governorship of California and then the presidency.

Reagan was later credited with having almost single-handedly pulled the Republican Party from the ashes of that Goldwater defeat. He continued to intone the freewheeling Arizonan's message but without its sharpest edges. The politically wounded Goldwaterites regrouped and found new allies years later in the tea party movement.

Like the old rabid Barry forces who survived amid the demise of the liberal Republicanism of Nelson Rockefeller and cohorts, the newer recruits have also adopted an uncompromising style and agenda that have brought the party to its current state. More prudently, however, they cling to the safer Reagan rather than to the quirky Goldwater as their patron saint.

The man who will be nominated in Tampa, Mitt Romney of Massachusetts, was widely associated with the moderate wing of the GOP the first time he ran for president in 2008. But after much political contortion during this year's primaries, he will offer himself as a faithful disciple of the whole gamut of conservative Goldwater/Reagan orthodoxy that will be on display at this week's convention.

It is opening amid considerable distraction and chagrin over the inane remarks of the Republican Senate nominee in Missouri, Rep. Todd Akin, espousing the unqualified abolition of abortion even in the case of what he bumblingly called "legitimate rape." Mr. Akin so far has rejected the call of Mr. Romney and his prospective running mate, Paul Ryan, to withdraw from the Senate race for the good of the party and of its chances of regaining control of the Senate this fall.

At the same time, however, the writers of the convention platform meeting in Tampa went ahead and adopted Mr. Akin's position on rape, if not his loony rationale, in its 2012 platform two days after he had blurted it out in a local television interview. The plank to be voted on by the convention continues the previous party position, saying "we assert the sanctity of human life and affirm that the unborn child has a fundamental individual right to life which cannot be infringed."

The plank thus allows for no exception in cases of rape, though Mr. Romney himself has said he would favor that exception. The timing of the Akin embarrassment could not have been more unfortunate for a party that increasingly takes on the mantle of extremism that old Barry so proudly asserted nearly half a century ago.

Jules Witcover's latest book is "Joe Biden: A Life of Trial and Redemption" (William Morrow). You can respond to this column at juleswitcover@comcast.net.