it can HELP, but it ain't gonna do much if you are in a seriously dense cloud of VX gas, but that is extremely remote likelyhood. Stuff like that is so horrendous that the folk using it, unless very very careful, will die before they even release it, that's why they use it on missiles etc so it goes off far away from you. Terrorists would find it hard to get both the gas AND a proper delivery system unnoticed into your country. That stuff is seriously complex, needs a lot of equipment etc. Against more likely weapons like Mustard gas, some radiological stuff, a sealed room will help. It's just not like, guaranteed. Could well save your life, even against nerve gas if the release is thinned by time it gets to you and in low amounts. But you also have to seal the place correctly (air conditioning....) and not kill youself from lack of oxygen. But what folk ahve to realize is that terrorists ARE terrorists because they are inneffectual a*sholes! They cannot do much. However nasty this sounds, 9/11 was a blip, 20,000 americans are murdered each year, 9/11 killed 1,300. An attack by a major power would be devastating, kill millions, but terrorists are absolutely tiny in number and almost totally USELESS to their cause. They are counter productive. Sounds callous? Sorry but you should worry FAR more about your family being hurt or killed in car accidents, from smoking related diseases or alcohol abuse. terrorists kill miniscule amounts of folk each year compared to those three. terrorists use TERROR, because they can't actually DO very much, it's all based on fear, panic and alarm.

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