I also think that Ezra doesn’t really grapple with the strongest arguments on the other side. For one thing, although there are examples of presidential offensives that failed (George Bush on Social Security privatization), there are also example of presidential offensives that succeeded (George Bush on going to war with Iraq).
Drum doesn’t cite any public opinion data. In this case, the data fails to support his argument. In the run-up to the beginning of the Iraq War, public support for the war did not increase. It polarized along party lines, just as happened with Social Security privatization. Here is a graph from Gary Jacobson’s book:
Although there was a brief rally effect right at the war’s outset, support among both Democrats and independents actually decreased in the months preceding the war. This is not a case where presidential rhetoric successfully persuaded the public.