The Pitters' Place

Can someone explain the TPP? I skimmed the wiki article so I guess I get the general idea. But why are so many people so opposed to it? I've seen plenty of people say that they won't support presidential candidates who supported the TPP. Are there others who DO support it? Is it something that's actually been passed or just an idea that might happen?

I have found this comic to be a very solid explanation.

http://economixcomix.com/home/tpp/" onclick="window.open(this.href);return false;