Victor Davis Hanson wrote this week: Sometimes retired generals are deified. Ulysses S. Grant and Dwight D. Eisenhower won two presidential terms in landslide elections. At other moments, war heroes such Generals Douglas MacArthur and Curtis LeMay were vilified as near insurrectionaries for their blistering attacks on sitting presidents. Recent days amid the violence and anger following the murder of George Floyd by Minneapolis police here in the United States have seen the potential for a military coup against Donald J. Trump raise its ugly head. Should we be worried? Yes.