Perhaps it started under Eisenhower, to some extent, but its metastasization increased a great deal under Reagan.
The author argues that it Metastasized as an Republican only thing under Nixon when the One Nation Under God movement split, and became the sole providence of the Republican party. I even won't disagree with you that it became a bigger thing under Reagan, but with so much history behind it I am not quite sure how you can call that a revolution. That seems like slow, gradual change to me, but perhaps we just have different definitions of radical change.
It's not JUST the interventionism, I misspoke because I can't type quickly on my phone, so much as it is the whole ethos of America needing to exert its military might as a moral force for democracy and freedom across the world. Prior to Reagan, the U.S. certainly intervened in a number of situations, most notably Vietnam, but one can at least say that there was geopolitical triangulation happening, given the U.S. desired to check the expansion of Communist imperialism. Reagan not only prolonged the Cold War by reigniting Soviet hardliners, but began the neoconservative spiral that eventually birthed the Iraq War - which, while not a RADICAL break from American interventionist policy with respect to their oil supply, was sold to the public on the grounds that Saddam had Weapons of Mass Destruction that could eventually be used against America and its allies, and that we therefore had a moral duty to overthrow him and install a democratic government, democracy being construed as an institution inherently friendly to American interests. Had Reagan not turned the ideals of American exceptionalism and moral destiny up a number of notches, I don't think the public could have been so readily snookered into what was essentially a second Vietnam War on such spurious philosophical and practical grounds.
I think the Cold War was very ideological and one of the main reasons for the fight against Communism was to stop its spread and save Democracy and Freedom around the World.
As for the Iraq War, I assumed that he was talking about the first one, Desert Storm, because he was talking about the first Bush in his post. I would also argue that you can consider that war pretty a fairly realpolitik decision.
And again, an ideology driven foreign policy that wants to spread democracy throughout the world is nothing new or radical to our history. That was one of the main arguments for the Mexican War, that we should attack Mexico and conquer this new territory to spread democracy and freedom. Same with a lot of our interventions in Latin America during the 19th Century. So I don't think Iraq War 2 is a radical change because that is a strain of foreign policy thinking that has been present in our nation since its founding. The Jeffersonian Republicans were all about helping France and supporting them in their wars to support and spread Democracy and freedom. Luckily, Washington and Adams took a more realpolitik approach.
I don't disagree that Reagan was just the conduit of ideas that had been in the ether for a long time, but he not only implemented them, he instituted a rightward shift of the national political conversation so complete that even the opposing political party is limited in the kinds of changes it can propose because so much of his philosophy has seeped into the political unconscious of so many. He also is the one that shepherded the Republican Party away from responsible curtailing of the federal welfare state to becoming a party that both kept the welfare state in place while drastically cutting taxes and increasing military spending, knowing that this would endear them to voters (the dreaded "two Santa Clauses" theory) while deluding themselves into buying into the movement conservative bullshit that tax cuts and deregulation would drive prosperity and pay for themselves. Neither turned out to be true, and Reaganomics are thoroughly discredited, but they still form the basic basis of the economic policy of one of the two main political parties of the country.
I think we might just have different conceptions of radical change because the Right have used the same sort of rhetoric to discredit the welfare state since the New Deal. It simply worked in the 1980s because the economic downturn discredited the left while the boom in the 80s 'supported' reaganomics.
I would agree that voodoo economics was a change, but again, maybe we disagree on definition because I woundn't consider that a huge change.
Reagan certainly was not a RADICAL change, in the sense that he didn't rewrite the Constitution or anything like that, but I'd say the changes he brought to the country's political culture were certainly radical. It wasn't called the "Reagan Revolution" for nothing.
I think Reagan was simply a culmination in the reaction against the New Deal that the Right has been working towards for a long long time. This shift in the political culture was greatly helped out by the Cold War anti-communism and the economic cycle. Again, I wouldn't consider this revolutionary because it all it really is a shift back to the values and ideals before the New Deal taking a more prominent role.
As for the Reagan Revolution, I think people like to overuse terms like that and the vast majority of people don't pay attention to gradual historical change. Again, we might just have a different definition of what constitutes a radical change.