Point is, your argument is only ALMOST on solid ground. Sure, sophisticated chemicals and biologicals are not easy to make but nerve agents ARE... and they are pretty awful things. There's more to be said, but duty calls and so does my nice warm bed. Work is beckoning in the morning.
Points 1. and 2. you mention above are "true", however, neither has anything to do with the subject under discussion, which is the right of people to own guns, or other arms (including WMD's) for self-protection from dangerous criminals and/or tyrannical governments.
For point 1., chemical nerve agents are not only relatively easy to make, you can buy them over the counter in any Wal-Mart in the insecticide and household cleaner departments. BUT, and it's a very big BUT, in the "real world" people don't try to use them for personal protection, although a woman spraying a would-be rapist in the face with a can of Raid would be perfectly okay. For point 2., the release of sarin gas in the Tokyo subway by the AUM Shinriko cult was a terrorist attack, not an act of self-defense. Their "crime" was murder, no matter what tool they used to do it, and it's happened just once. By your logic, since San Francisco was once destroyed by an earthquake, and we know theoretically that another could occur at any time, then we should just evacuate and abandon the city. After all, the risk is "real".
The bottom line is you seem to have completely missed my "point" from my original post, and ironically, your points actually supported and illustrated mine perfectly. The examples you gave are theoretically are infinitely remote, they simply are not a problem in "the real world".
As I pointed out in my previous post, the only people who are actively trying to acquire WMD's are those wqho are already embarked upon far more murderous missions: terrorism, and in the case of governments, acts of war and aggression. There are far more relevant laws under which to pursue these people than through gun regulations.
Trying to tie these types of actions and crimes to the issue of gun control is simply dishonest sophistry, and those who advocate these types of arguments reveal themselves clearly. They're not concerned about the rights and lives of their fellow human beings - they're only interested in controlling them, and any pretext, however specious or absurd, will do.