How insecure do you have to be to hang flags all over the place to demonstrate your "patriotism"? (I know the purpose is not to demonstrate patriotism) But seriously, shouldn't the first question be "Why do you need to do this? isn't your pride and pleasure in your country enough?"?
It’s loudly proclaiming which side you’re on - advanced dick waving.
But which "side" is it? None of these people are giving me the sense that they have even the modicum of insight necessary to appreciate relevance of the "Are we the baddies?" sketch from Mitchell and Webb.
When I was new to work I was chatting to a senior manager who always wore Hawaiian shirts to work (in a techy role). He said he had always tended to dress smartly for a while after he'd been promoted, then revert to type once he felt established. Informality is a major flex. Same for patriotism.