And the people with guns receive their orders from the President and lower hierarchies of the executive branch.
While police are generally 'executive' they are often supposed to take orders directly from the courts. Most warrants begin with phrasing in this manner: "[any] peace officer shall arrest..." Some states also allow judges to directly order peace officers to make arrests for offense committed in the judge's presence without a warrant being drawn up first. Even if their boss is telling them to not do it, they should ignore the unlawful orders and get along with the handcuffing, but it won't ever happen.
Just like how trump was soft-handed in every courtroom for the last four years, I can't imagine any judge right now ordering his appearance at court or an arrest. Anyone with half a brain knows that he would ignore it, and it would go to the supreme court and they would rubber stamp whatever he had done as being not subject to the law because he was 'acting in the presidential capacity.'
I hate you so much right now.
/said while brushing legs off repeatedly