This is arguably a death threat, and the SS [or US Marshalls?] should question the perp with the hairy eyebrow and at least leave him with a verbal warning that a repeat of this nature against any public figure would be prosecuted.
— BUT —
Kill the poison ivy at the root. Maxine Waters needs to be removed. And that process should be publicly discussed during this campaign. Make Waters an issue — spotlight. Poster ‘Girl’.