A masked guy breaks down your door w/o an Article III warrant absent exigent circumstances? Yeah, I’d agree. Trick will be that pressing the murder charge would be federal since a federal agent dies in the line of official work (though illegal), which would give the president grounds to push for death.
Cowards, yes! 90% of them will shit their pants and shoot themselves or team kill. They chickened out of military service and are too stupid to become police officers.
Anecdotal reports are that the worse cops in a number of police departments quit to join ICE. Like the cops that other cops don’t like.