I hope there is no more destruction

"Fool me once, shame on you. Fool me twice, shame on me."
Montgomery Scott, Chief Engineer, USS Enterprise

I heard on the radio that intelligence suggest that this may be the first of four and that if so a biological weapon threat may be probable. Have any of you heard anything similar? (No, I do not mean to create panic and further fear.)

This war is difficult in that we can not see or easily identify the enemy. But we can try to think like them and try to cut them off. Now that you think about it, it is probably not that difficult to get a knife on a plane (but it is still pretty difficult to get a firearm on the plane).

Any thoughts about what could be next? Railroads? Other infrastructure?

Aren't there different kinds of gas masts? Those just for like tear gas and smoke and those that protect against biological threat. Anyone know how much a gas masks costs?