The Republican presidential sweepstakes -- volatile?  No American Thinker readers need be told that.  But Alex Roarty adds historical perspective at today's National Journal.  Roarty had been writing that the 2012 GOP presidential contest might be the most unpredictable since 1964.  That year, Barry Goldwater emerged as the GOP standard-bearer over Nelson Rockefeller. 

Now Roarty opines that the 2012 scramble for the GOP presidential nod may not only eclipse 1964, but may best GOP contests as far back as 1930.  Why is this?

For a reason that Roarty doesn't address.  The political plate tectonics are shifting under the GOP in ways that they haven't since 1964.  The Goldwater ascendancy marked the beginning of modern popular conservatism as a tangible electoral expression.  That expression's high-water mark was Reagan's presidency, which ended nearly a generation ago. 

Grassroots conservatives and tea party activists aren't pushing to reinvent Reagan's conservatism, but to align its electoral expression closer to the principles that Reagan advocated.  Ronald Reagan's adherence was first and foremost to founding principles, and that's where Reagan's heirs are tending.  The grassroots conservative movement aims to reinvigorate the anemic Republican Party as a lean, mean, principled conservative fighting machine. 

What we're witnessing in this year's GOP presidential contest isn't volatility because conservative voters are "fickle," as Roarty and his National Journal colleague Ron Brownstein both suggest.  Nor is 2012's GOP presidential dustup just because of the fracturing of the conservative field (as opposed to Mitt Romney's establishment faction).  Nor do plentiful GOP presidential debates and social media entirely explain the volatility.    

Politically, we're seeing the death throes of the old and the birth of the new in the Republican Party.  The fractured conservative presidential field is making that birth harder, but it's happening, whether or not it's realized fully in 2012.  The process actually started in the 2010 congressional elections.  The intellectual and moral dynamic belongs not to old guard Republicans but to invigorated, principled grassroots conservatives throughout the country.  In other words, it's not a matter of if grassroots conservatives will succeed in capturing the GOP, but when.          

As in 1964 -- and before that in 1896 (the McKinley realignment), change is coming -- big change to the Republican Party.  And if those earlier critical years are harbingers, it means big changes in governance for the nation in the future, near and longer term.