Can't imagine what possible difference it would make whether you watch or not. The only meaning it would have would be whatever meaning you give the action of watching. "Endorsement"? You mean, if someone peeks in the window and sees you watching the inauguration, they'll take that as an expression of support for the new unpresidented president?

If you feel like watching it, watch. You can always tell yourself you don't want to miss it if he slips on a banana peel or if someone throws a pie in the buffoon's face.