A question I've always had that is highlighted by the whole Glaser-Taiwan imbroglio is, is there a definitive history of how "realism" became a philosophy of restraint?

I mean, my reading of realism, from grad-school days, is that it recommends the pursuit of power and domination without moral constraint or interest.

I always thought that according to realism, the US should have maintained its forces in being in 1945, built up its stockpile of atomic bombs, and annihilated the Soviet Union by 1950 at the latest.

According to realism, the US should have killed tens of millions of Chinese in 1950 for even thinking about intervening in Korea. The same 15 years later over Vietnam.

The realist policy towards Iran today would be to destroy the nuclear facilities with the largest nuclear weapons we have, and then if there were any complaints, to destroy the 100 largest population centers as well. And so forth.

And yet, in the US, realism is now synonymous with restraint, to the point of isolationism.

I trace this back to Waltz and his opposition to the Vietnam war. He framed it as opposition to "diversions" and not caring about "peripheries." To me it always smacked of rationalization for the anti-war sentiment that was popular at the time.

Fast forward to my graduate education, John Mearsheimer's theoretical ideas seemed to justify the most ruthless intervention imaginable, but his policy prescriptions were as dovish as could be. Again, I interpreted this as a hangover of Vietnam.

But this now seems to be generally the case and accepted as true about realism. Even the younger folk are of this persuasion.

States do/should ruthlessly compete for power and use every means to destroy each other because that is the only path to survival. Therefore the US should never intervene anywhere and it would be fine if Iran got nuclear weapons and China conquered Taiwan.

Something for the sociologists of knowledge.

Post-script. I think it is related to the foundational motivation for arms control theory as articulated by Schelling and Halperin, namely to provide a hawkish, pragmatic sounding rationale for dovish policies.

S&H had to distinguish themselves from the beatniks and idealists who wanted to ban the bomb in order to get a hearing. Their rationalist framework serves that end, while recommending cooperation and constraints.