Let’s just come right out and say it: the Republicans couldn’t do a better job of tanking the midterms if they were doing it on purpose.Is it possible they are? Or have they just inherited their president’s gift for doing the worst imaginable thing at the worst imaginable time?I’m talking about the decision of Senate Judiciary Committee Chairman Chuck Grassley – a literal fossil at age 93 – to put Jack Smith on the stand Tuesday to testify under…