Appleseed, anyone?
Battle Angel Alita and its sequel have their share of politics too.

I second Fullmetal Alchemist... How about Anatolia Story?

I'd say these are kinda political.

Shina Dark
Hellsing - there is a political backdrop but it's far from the focus.
Gunslinger Girl - deals with political terrorism and stuff.
Dance in the Vampire Bund - I've haven't read enough to be certain, but judging by the description it seems like it will be at least vaguely political.
The Legend of Maian - scans just getting started, but seems to have a kinda political theme.
Vampire Juujikai - not political at all at first but sort of turns that way further along.

Tree + Taco = Tree taco.

These are the most political ones i've read that i can recommend:
Red River
Amatsuki
Tokyo Crazy Paradise
Full Metal Alchemist (the anime is really good as well)

From the manga: Good Luck, Demon King!

---Apothecarius Argentum
---+C: Sword and Cornett
---Yugo
---Strain

As they are political, they might not fit your liking.

Give a man fire, and he will be warm for a day, set a man on fire, and he will be warm for the rest of his life.

http://www.mangaupdates.com/series.html?category=Politics

everything here

No Say Hello to Black Jack? Ethical issues, political problems, etc. all laid out for you to ponder.

If you like BL... try... Ice Eagle Fire Hawk: slight understanding of politics, I recall... something that so many manga don't even try when they delve into said topics. >>;;

With very light political touch... Reimei no Arcana: another manga that at least understands what "territorial conflicts" are about... >>;;

gunslinger girl.. story bout european politic.. though the story is center in italy's politic and terrorism
kekkaishi.... a story of politic in a weird 'ground'.... very deep though. until now i still don't understand what all the older characters (the big bro included even though he is young) are really aiming for. while the young characters look as if they got carried around with it

Zettai Heiwa Daisakusen (shoujo) Leads unite to stop a war between their waring opposing countries

Second Eden and Akumetsu
Until Death Do Us Part?
Hetalia?
Battle Royale?
Sanctuary fits perfectly

its cold down here fam ~