I was complaining about this over lunch and Neil Sinhababu makes the point well:
He may not be the first person to blame, but Barack Obama deserves some criticism for letting the Arizona immigration law befall us. If he had left Janet Napolitano as Arizona governor instead of putting her in charge of Homeland Security, there’s no way this law would’ve passed. Instead, Jan Brewer took office, signed it, and is now saying that her state is under terrorist attack from illegal immigrants.
Additionally, we could’ve had Napolitano as a Senate candidate. How that would’ve affected John McCain’s votes over the past year and the 2010 Senate outlook is left as an exercise for the reader. The smart thing would’ve been to have somebody else do Homeland Security with the understanding that they might be asked to step out in two years, and that the Cabinet job would be Janet’s then if she put in a good showing but lost her Senate race. Similar things apply, mutatis mutandis, to Kathleen Sebelius at HHS and Tom Vilsack at Agriculture.
In terms of the political impact, having Vilsack running for Senate seems to me like the biggest deal. Iowa is a pretty liberal state. Not only did Barack Obama get 54 percent of the vote, but it went for Al Gore, went for Bill Clinton twice, and even went for Michael Dukakis. Tom Harkin proves that not only can Democrats win statewide in Iowa, but liberal Democrats can win. Of course Obama doesn’t have the power to force incumbent governors to run for Senate, but sticking them in the cabinet guarantees they won’t.