How does Twain create humor in tense situation of Pa's drunken rage in the cabin?

Pap is portrayed as a hapless drunk who mutters crazy things that border on satire and dark humor. Pap is drunk and makes Huck go outside and bring in all the supplies he has brought from town. Pap proceeds to drunkenly curse everyone he has ever met and spends a significant part of his tirade criticizing the government.