Sheesh, it's so tough to get through. The POINT of a Beslan or Madrid in the USA would be to INTENTIONALLY highlight the open border, and thereby blame the attack on Bush. To "Aznar" Bush.
The 30 border crossers (let's say 20 make it through) have only a phone number to call, memorized. They are dedicated terrorists, desiring martyrdom, so they will not give up the number to the FBI. I mean, the FBI ain't gonna behead them. Won't even say boo to them, actually.
So the 20 who make it through (this is SO basic!) make a call to a vacant house with a phone answering machine, with more instructions etc on it. The instructions are cryptic, leading to an address, other phone numbers etc (Do I really have to spell out such BASIC tradecraft? It's late.)
Anyway, the 20 wind up in a safe house. The "support cell" is probably only one man. He may have some "helpers" who have no idea about the plan, they just provide vehicles etc. Very tight opsec. If you see a flaw, just tell me. The support cell (one man) has accumulated 20-30 firearms over a couple of years. No problem. This is America!
(In fact, using easily and legally purchased weapons for the terror attack will be calculated to do even more political damage to Bush.)
Explosives: if you think this is hard, you don't get out enough.
Finally, the attack. Just for the heck of it, I'll tell you what I think a planner would do: go for a tower. They will want a prolonged siege, in a place where the govt can't keep the TV cameras away. Plenty of visibility for messages on sheets, dumping headless hostage bodies etc. Makes a hostage rescue op very hard. Pick a tower with a restaurant on top, for plenty of tourist-hostages, and food and water for weeks (no need to ask for outside food, which can be drugged.)
I'd pick the Seattle Space needle, for example. Just bust in guns blazing, like in Beslan. Kill a rentacop, and take the elevators to the top, and disable them. A few office towers in Texas also come to mind.
All you need are the "shooters" who can walk in "clean" from Mexico. Spanish-speaking Moroccans (as in Madrid) would be ideal.
Why do you feel it necessary to put down people who disagree with you? So far, I have only provided my point of view without making derogatory comments about you personally. You have a valid point of view and all I was doing was offering my view as to why I don't think this 30 man Chechec thing is likely. You seem to take the view that anyone who doesn't see things your way just doesn't understand as much as you. I don't think that is necessarily the case. Basic tradecraft does not include answering machines leading you to other places. Why would you need that? If I have the first number then I will simply call it and follow the directions just like the terrorist. It's also WAY too complicated and leaves room for errors. Contact instructions need to be simple and have a fallback. Messages leading you to other messages are ok for ransom demands, but don't cut it as good contact instructions. Basic tradecraft would be those Chechens settling in and then being contacted after a cooling off period. They would go to a library, get on the internet and create an email account. They would then deliver a benign sign of life to a predetermined e-mail address. If the terrorists have spent two or three years setting up these safe houses and cells I can't imagine them risking them like that with 30 Chechens crossing the border all carrying backpacks, most probably totally out of their cultural element and trying not to stand out. The obvious scenario to me anyway, would be to bring Arab terrorists in to the US one at a time over a period of a year or two and just let them stay as sleepers until such time as they are needed. It's just as easy as 30 Chechens across the border and a lot safer, in my opinion. The fact of the matter is, if one of those Chechens was arrested at the border the entire operation would have to be called off. If it wasn't then these terrorists are so stupid we have nothing to fear.