Jon Stewart in Heated Shouting Match in D.C. Over Vet Bill

Jon Stewart is fired up again in D.C. over the veteran bill he's fighting to get passed -- but this time, his anger was much more focused and raw than last week.

The former 'Daily Show' host got into a heated shouting match Monday just outside Capitol Hill, where he was facing off with conservative political commentator and media personality Jack Posobiec -- who apparently dropped in on Jon's ongoing lobbying efforts.

It's unclear what exactly precipitated Jon's wrath here, but one thing's for sure ... the dude is absolutely irate as he accuses Posobiec of acting in "bad faith."

A later video shows Jon in a much calmer state ... and Posobiec says cooler heads prevailed in the end. It sounds like whatever they were arguing over at first was resolved, because he actually shakes hands with Mr. Stewart.

Posobiec actually says he was on Jon and the veterans' side all along, and it seems Jon came to that realization too. What can't be denied is Jon Stewart's passion for this issue -- if his presence and powerful words alone weren't enough proof, take a look at the video.