I've long said that the differences between so-called establishment Republicans and grassroots conservatives are about more than tactics in budgetary battles with President Obama and congressional Democrats. The current Cruz-Rubio flap validates my position. Establishment Republicans have been enormously frustrated with the grassroots for wanting to call Obama's bluff in these budget battles to the point of allowing the government to shut down. They have maintained this is a fool's errand that will only help Democrats because shutdowns will always be blamed on the GOP, supposedly the party of limited government. The establishment has been particularly derisive of Ted Cruz...