The best letters — and there are many — come from the typewriter of the public Schlesinger, the fighting liberal, especially when he’s jousting with a provocative antagonist like William F. Buckley (“You remind me of my other favorite correspondent, Noam Chomsky”) or, even better, arguing a matter of principle with a friend at the breaking point. The Vietnam War, which shattered the New Deal coalition, produced unsparing letters between Schlesinger, who became a vehement opponent of the war, and old friends like Alsop and Henry Kissinger, as well as a remarkable exchange with Schlesinger’s longtime liberal ally, Vice President Hubert Humphrey, during the 1968 campaign. “Don’t overrate yourself, Arthur,” Humphrey wrote in July, shortly before the disastrous Democratic convention in Chicago. “No one’s trying to blackmail you or anyone else into coming over to support my candidacy. On the basis of your earlier and more mature liberal convictions, you ought to be supporting me, but undoubtedly something has happened in your life that has made you angry and bitter.”
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