Those postulating that one side or the other would never do this or that assume that both sides have got and can exercise full control of those fighting on their behalf - this is a mistake because, put as simply as possible, they don't exercise anything like that degree of control.

A hit by an artillery or rocket barrage on a rebel chemical weapons storage site? Doubtful, because chemical and biological munitions are normally stored unarmed, the weaponised agents are only filled into the warheads, shells and mortar rounds immediately prior to use (Remember the 45 minute claim? That is what that was all about) - How do you destroy chemical or biological agents? Extreme heat - very few things get more extreme in temperature than being at the centre of a high explosive detonation - the weaponised agents would be destroyed if their storage vessels were ruptured.

Everybody is going on about this latest attack as being the first - It is not I believe that it is the fourth reported instance - the reason the UN weapons inspectors are in the country is because they have a mandate to inspect the sites of the first three attacks, not this latest one.

To answer the question posed by the opening post:

"I asked him if he could think of anything other than chemical weapons, or a neutron warhead, that could cause the death of a great many people within minutes without trauma."

1: Indirect concussive blast or shock wave
2: Asphyxiation caused by an explosion and fireball robbing a space of oxygen.

Both of the above were noted to have occurred in cellars during the allied bombing attack on Hamburg in 1943. The bodies found did not bear a mark on them.

It will be interesting to know what chemical or biological agent was used, if it proves to be VX then there will be some extremely red
faces around, as in that part of the world VX could only have come from one source - Iraq.

If the Syrian Government is responsible and it is decided to mount a targeted response, then do whatever it takes to assassinate Assad himself - the ensuing leadership squabble should impede any activities of the pro-government side. But better by far just to stay clear of it, we would be damned either way, it is a no-win situation. It is their fight so let them get on with it - or better still let Russia and China step up to the mark and end it - but there is about as much chance of that happening as there are of pigs flying.