When you read something like this, it just leaves you wondering how to react. This is a Washington Post article detailing the discovery of chemical weapons precursor agents in a warehouse in Mosul.
I perused a Daily Kos diary about this topic, and in the comments, I noticed that many Kossacks are wary of going full-bore into the idea that these are weapons-grade agents, as opposed to being innocuous agricultural chemicals, such as pesticide precursors. While I understand the concern, I have no reason to disbelieve the Pentagon's claims on this simply because the discovery of chemical agents snuck in by the insurgents simply does not help this administration or the Pentagon--instead, it reminds us of the bitter irony that the administration has, by its invasion created the very situation in alleged response to which invaded in the first place.
Add to this the simple fact that no mention of this discovery has been made on any of the typical right-wing sources (Drudge, RedState, Fox, Powerline, Newsmax, etc.), whereas randomly hollow tubes that that pre-dated the invasion were frontpage news for these places before, and you get the impression that this is a piece of news that simply does not bode well for current administration policy.
The more interesting developments from this story (should these chemicals prove, in fact, to be weapons precursors targeted for use against American and Iraqi soldiers) will be if an investigation into their origin tracks them down to a foreign country (that is to say, most likely Syria or Iran). Would this give the administration the excuse it needs to initiate regime change in either of these two countries? Keep in mind that Bush just today reiterated his position on Israeli TV (in stronger terms than before) that military action against Iran is most certainly on the table. If so, would they do it, and how much public support would they have?