In this passage from “civil disobedience,” what main point is thoreau making?

i have paid no poll-tax for six years. i was put into a jail once on this account, for one night; and, as i stood considering the walls of solid stone, two or three feet thick, the door of wood and iron, a foot thick, and the iron grating which strained the light, i could not being struck with the foolishness of that institution which treated me as if i were mere flesh and blood and bones, to be locked up… i saw that, if there was a wall of stone between me and my townsmen, there was a still more difficult one to climb or break through before they could get to be as free as i was. i did not for a moment feel confined, and the walls seemed a great waste of stone and mortar.

it is not logical to lock people up for not paying their taxes.

it is impossible to take away peoples’ freedom just by locking them up.

a short term in a jail is preferable to being with neighbors who don’t understand you.

people should have longer jail terms for serious offenses.