Is One Permitted to Punch a White Supremacist in the Face?

(1) Ben Zoma says:...Who is the mighty one? He who overpowers his inclination, as it says, "slowness to anger is better than a mighty person and the ruler of his spirit than the conqueror of a city." (Proverbs 16:32).

(18) If a man has a wayward and defiant son, who does not heed his father or mother and does not obey them even after they discipline him, (19) his father and mother shall take hold of him and bring him out to the elders of his town at the public place of his community.(20) They shall say to the elders of his town, “This son of ours is disloyal and defiant; he does not heed us. He is a glutton and a drunkard.” (21) Thereupon the men of his town shall stone him to death. Thus you will sweep out evil from your midst: all Israel will hear and be afraid.

(5) The wayward and rebellious son is judged on the basis of his end. He should die innocent and not liable, because the death of the wicked is beneficial to them and beneficial to the world; but for the righteous, it is bad for them and bad for the world.

(1) If the thief is seized while tunneling, and he is beaten to death, there is no bloodguilt in his case.

...if it is as clear to you as the sun that he is not at peace with you, then kill him. But if it is not, do not kill him. Another version is taught:...if it is as clear to you as the sun that he is at peace with you, do not kill him, and if not, kill him...

(11) Some time after that, when Moses had grown up, he went out to his kinsfolk and witnessed their labors. He saw an Egyptian beating a Hebrew, one of his kinsmen. (12) He turned this way and that and, seeing no one about, he struck down the Egyptian and hid him in the sand.

(1) While Israel was staying at Shittim, the people profaned themselves by whoring with the Moabite women, (2) who invited the people to the sacrifices for their god. The people partook of them and worshiped that god. (3) Thus Israel attached itself to Baal-peor, and the LORD was incensed with Israel. (4) The LORD said to Moses, “Take all the ringleaders and have them publicly impaled before the LORD, so that the LORD’s wrath may turn away from Israel.” (5) So Moses said to Israel’s officials, “Each of you slay those of his men who attached themselves to Baal-peor.” (6) Just then one of the Israelites came and brought a Midianite woman over to his companions, in the sight of Moses and of the whole Israelite community who were weeping at the entrance of the Tent of Meeting. (7) When Phinehas, son of Eleazar son of Aaron the priest, saw this, he left the assembly and, taking a spear in his hand, (8) he followed the Israelite into the chamber and stabbed both of them, the Israelite and the woman, through the belly. Then the plague against the Israelites was checked. (9) Those who died of the plague numbered twenty-four thousand. (10) The LORD spoke to Moses, saying, (11) “Phinehas, son of Eleazar son of Aaron the priest, has turned back My wrath from the Israelites by displaying among them his passion for Me, so that I did not wipe out the Israelite people in My passion. (12) Say, therefore, ‘I grant him My pact of friendship. (13) It shall be for him and his descendants after him a pact of priesthood for all time, because he took impassioned action for his God, thus making expiation for the Israelites.’” (14) The name of the Israelite who was killed, the one who was killed with the Midianite woman, was Zimri son of Salu, chieftain of a Simeonite ancestral house. (15) The name of the Midianite woman who was killed was Cozbi daughter of Zur; he was the tribal head of an ancestral house in Midian. (16) The LORD spoke to Moses, saying, (17) “Assail the Midianites and defeat them— (18) for they assailed you by the trickery they practiced against you—because of the affair of Peor and because of the affair of their kinswoman Cozbi, daughter of the Midianite chieftain, who was killed at the time of the plague on account of Peor.”

"Assail the Midianites" -- Why? Because they assailed you. And upon this basis the Sages said, "One who comes to kill you, rise up and kill him."

(17) Remember what Amalek did to you on your journey, after you left Egypt— (18) how, undeterred by fear of God, he surprised you on the march, when you were famished and weary, and cut down all the stragglers in your rear. (19) Therefore, when the LORD your God grants you safety from all your enemies around you, in the land that the LORD your God is giving you as a hereditary portion, you shall blot out the memory of Amalek from under heaven. Do not forget!