Here's the letter I just sent off to the WaPo. Since they get so many letters, it probably won't see print, but I think it's got a chance; we'll see.
Some opportunistic Republicans claim that the discovery of some mustard gas shells from the Iran-Iraq war means that the infamous WMDs have at last been found. This claim seems to rest on a term-of-art definition: that WMDs include any nuclear, biological, or chemical weapon, regardless of its lethality or destructive power.
This is a fundamentally dishonest rhetorical gambit. The Bush Administration and its supporters did not educate the public about term-of-art meanings of "weapons of mass destruction"; rather, they actively played up the vernacular meaning of the phrase - weapons that could wreak extraordinary death and destruction, well beyond the capability of conventional weapons.
For instance, just between March 15 and March 19, 2003, President Bush described Saddam's weapons stash as "the weapons of mass murder," "some of the most lethal weapons ever devised," "biological and chemical agents...capable of killing millions of people," and claimed we were invading Iraq "to defend the world from grave danger."
The aging mustard gas shells bear no resemblance to the threat Bush described. Mustard gas isn't even particularly lethal, though it's still nasty stuff. It's a potent skin blistering agent that can incapacitate soldiers on the battlefield, thereby reducing the effectiveness of their combat units. If it gets into one's lungs in strong enough concentrations, it can be lethal, absent effective treatment. But a weapon of "mass destruction"? That's absurd.