Don't mail the fish. All goes a mailroom and no one really sees it or will talk about it outside of the White House.

Toss the chum over the fence. Make it a public spectale so everyone can see it. Hard to ignore a growing pile of chum on the White House lawn. Make the rest of the world talk about how the White House got chummed. Nothing frustrates a fascist faster then being mocked and humilated in public.

Edit: The amount of birds that will show to eat all that chum and then proceed to shit everywhere too.