What does Abbey mean by "pox vobiscum," and "swinish politics?"

He clearly is disgusted with people on both sides of the flag, and sees politics as a "ball and chain" that perhaps, keeps us from being free. In any case, this is just a heads-up from Abbey, who is quite opinionated about the US government. The meaning of the latin term pox vobiscum appears to have several meanings, but in this context, it seems that Abbey's comment on swinish politics means "peace be with you."