Under three of the last four presidents, including now Joe Biden, Vladimir Putin has chosen to take military action against Russia’s neighbors. There has been only one exception, namely Donald Trump. A big part of Biden’s pitch to voters in 2020 was that he would bring a return to foreign relation norms. America would be back, the adults would be in charge, etc., etc. Well, here we are, norms and all, and yet Putin is still on the verge of an incursion into a U.S. ally, Ukraine. Another way of saying normal is predictable. Norms are after all a set...