He's right.
There's nothing they will not do to promote their goals.
Socialists have:
Burned down their own legislature building to blame and thus outlaw other socialists (Reichstag fire blamed on commies)
Use people as slave labor and starve them to death (Democrats in the early 1800's, National socialists in 1940's Germany)
Simply steal their food to murder them. (Stalin's Holodomor in Ukraine)
Discover their cultural revision plan killed 22,000,000 peasants and decided to continue course the next year, killion 20,000,000 more (Mao See Dung)
Murder the educated (Pol Pot, Cambodia, Hitler, Germany, elsewhere)
Murder the inconvenient (Rodents in USA and abortion, National Socialists and the mentally deficient)
Imprison dissidents for dissidenting (sounded cool) (Cuba and every other socialist paradise)
Nationalised and then ruined industries. Venezuela and just about every other socialist paradise.
Created imaginary hate crimes. (USA)
Lied to children in school. Every socialist regime in history, including the US.
Destroyed their economy.
Lied to get into office.
Stolen the office in the end (Hitler, Castro, Bidet)
Kept political prisoners (Wilson - Eugen Debb jailed for speaking against US involvement in that stupid europeon war.)
Name something you think is too low the socialists would never do it.
You've just given the Rodents a new bar to shoot for.