[VLM]

The thing I don't get, is if you know there are multiple devices, any opfor with half a brain is going to put them in the mass transit for follow up. So why evac people when sheltering in place is almost certainly safer? The TLDR is don't create a juicy concentrated target when you know for certain that someone is currently aiming at juicy concentrated targets.

Also if its an ongoing event, shelter in place means people pay pretty close attention to their environment, but scrambling in terror every random direction means a great opportunity for the opfor to drop something bad in the chaos and possibly escape.

I'm not saying lock down everyone for hours (days?) or don't evac a known bad location, but...

[Kequc]

It's easier to destroy than it is to create, for example create safety for the people there.

People outside a certain radius of the initial attack are almost certainly safer. The only thing you can do is get everyone out of the area. Keeping everyone there it seems... I'm confused about what the goal would be. You've got to move everyone out of there eventually so do it. I'm just trying to picture the huge amount of resources it would take to try and quarantine.

[taurath]

Transit is much harder and has a much stronger security presence - people in general are also far more alert for suspicious packages. It would be much tougher I'd think to get something like this onto a subway rather than a huge crowd.

[VLM]

Whoops I looked it up and apparently a "mall" in boston is what the rest of the world would call a boulevard or parkway. So they're actually evac a street lined with trees. My worry was it they're shoving people in immense lines thru the doors of what the rest of the world would call a "mall" making a tempting target for the opfor.

I am surprised its verified to be packages and not dudes wearing vests or whatever. There's no way to avoid the issue that getting the crowd to stampede means certain targets of opportunity will be very busy. If I were in Boston there's no way in hell I'd set foot on any mass transit until the evac is over.

The original point still stands, that people mostly sittin down can't get into too much mischief, "everybody get up and run around" results in huge opportunity for chaos, because not just the good guys, but the bad guys too will be up and running around.

[asynchronous13]

"mall" meant walkway or promenade for a long long time. It's only very recently that "mall" became short-hand for "Shopping Mall".

[hartror]

Actually Boston uses "mall" in the same way as the English and Australians.

[mindcrime]

It's not that uncommon in other parts of the US either. In Raleigh, they commonly referred to part of Fayetteville Street as "Fayettevill Street Mall".

[jlgreco]

Famously there is also the National Mall in DC; the area between the Washington Monument and the Capitol.

[jonemo]

And of course The Mall in London: http://en.wikipedia.org/wiki/The_Mall,_London

[jleader]

"people mostly sittin down can't get into too much mischief"

Except the psychological stress of sitting quietly near where a bomb just went off is probably much worse than heading for home. I imagine that the police manpower needed to actually keep people from leaving would be substantial.

The alternative isn't "everybody get up and run around", it's "everybody head for home, where you feel safe." I know if I were police chief, I'd think long and hard about the trade-offs before I tried to stand in the way of people trying to get home. After all, they're going to have to go home eventually.

And we know of one location where the opposition is known to have planted bombs; why would you want to keep large numbers of people around that location? Why not disperse them to their homes, so they're not such a concentrated target?

[r00fus]

That's assuming normal traffic flow. As someone famous said "quantity has a quality all it's own" - in large traffic flow conditions (as is the case with an evacuation), are all the same security precautions taken? Can they be sustained without a huge bump in the security staff? If new security staff are used impromptu, will they follow the same stringent standards?

I agree with VLM - these people should have been secured in place and not herded through a chokepoint in a rush.

[rdl]

I think the difference is there isn't only a single route for people to evac the mall. It would be insane to have an area where there's several bombings in a large area, with one gateway out, and to then encourage everyone to bunch up at the gateway.

[calinet6]

I grok'd your confusion about "mall" but just so you're aware, almost no one used the subway after the event. Everyone walked in a dispersed fashion. I did as well and kept to the back alleys and off the main race course. It was actually pretty ideal I think, people did well.