I don’t think there’s any meaningful strategic interaction on electoral politics. It’s never “if he does X, you should do Y.”
Just do Y. If Y helps you it helps you. Do stuff that helps you. You can’t “defend” against anything or prevent your opponent from doing anything. There’s no inoculating yourself against an issue (like, say, by voting for a draconian immigration bill). All of that West Wing-style drama stuff is a bunch of crap.