CNN has located dozens of videotapes documenting the history of the al-Qaeda terrorist organization, including tests which show chemical weapons tests on dogs. Based on the evidence, it appears as though al-Qaeda has been testing a nerve agent similar to sarin.
This discovery is disturbing, but not necessarily unexpected. Al-Qaeda was pursuing whatever methods they could to kill as many Americans as possible. That includes nuclear, chemical, and possibly biological weapons. Fortunately, their attempts to get ahold of nuclear materials failed miserable (as far as we know), but the discovery of these videos confirm that al-Qaeda once possessed chemical weapons, at least in small quantities.
Fortunately, al-Qaeda can no longer travel freely, and no longer can operate as they once did. Still, with this discovery, one wonders what other deadly weapons al-Qaeda had managed to get their hands on.