Yeah, Nast's hatred of the Irish is not too surprising, given the times, but man, to see a guy who kept preaching tolerance most of his career to not even realize the hypocrisy of his actions...it's quite sad.

http://www.thomasnast.com/

The anti-irish imagery is fascinating. Aside from the political reasons mentioned there were two other reasons why Nast was so hostile towards the Irish. Firstly as a Protestant German migrant the Irish migrants were a direct economic threat to other migrant groups and were Catholic in the main (19th C America was very anti-Catholic). Secondly Nast actually traced many images drawn by Sir John Tenniel of 'Punch' in London, which was well known for its hostile representation of the Irish.

http://www.guardian.co.uk/cartoons/stevebell/0,,2258187,00.html

But yeah, both are clear picks for a list like this.

or perhaps Gillray is a better starting point: http://en.wikipedia.org/wiki/Image:Caricature_gillray_plumpudding.jpg

Nast clearly followed in their footsteps, while adding an American twist.

Among current cartoonists, you might want to consider Steve Bell. His cariacture of John Major: http://www.artthrob.co.za/03nov/images/bell01a.jpg is the most effective I've ever seen in skewering a politician's public image.

Actually in classic texts of Latin and Greek (from which we borrow these words and style) redundant use of directions was part of the style. To say I go out in Attic Greek for example is: ek ekebaino, literally "I outgo out"
Unrelated to comics but whatevs

While they're not Olyphant, please remmeber Gary Trudeau and Berkeley Breathed this month, too!

*Snark* And Judd Winick, too. * Snark*