I guess you can't plain for all eventualities. The immediate response of race staff and first responders was amazing.
I am sure we have all followed it on the news so I don't want to talk about the bombs or bombers.

Like many I watched mesmerized. But the questions going through my mind were probably a little different.

Why was the side fencing near the finish setup with scaffolding and wood/wire picket fences, with the scrim hung on the inside?
Was it to withstand the pressure of a crowed that might have knocked over standard french barricades?
Was it to provide a 6' buffer zone between the runners and crowd?

What were all the people in yellow jackets doing who were spaced out every 15 feet before the finish?
Did they have that many volunteers they had extra people just to clap people in?

When we have a large number coming across a marathon line we have people working double-time on water, medals, medical etc, but all AFTER the finish line.
(Thank god we no longer have to clip of their chips.) Even so, we don't have hands to spare.

On the big marathon where I help manage the finish we keep EVERYONE other than one or two official finish line photographers,
and by EVERYONE that includes various media and TV, even All Access passes, back behind the finish line.

People are either behind the side barricades or behind the finish.
Even then, like most big races, we have a clear deceleration zone, a media setback line, and then a series of controlled zones after the finish.

Than I asked my self, how did they just stop the rest of the race?
Being pulled up short, when you can see the finish, that must have stung.
I doubt we have the logistics in place to just turn off a race of like that.

Than I thought, how DO you handle it?
Do you ask everyone at the finish to disburse and flee, or does that just cause confusion and cause people to get in the way of emergency traffic?

Do you re-route runners to the baggage check so they can get their stuff?
OR do you immediately abandon and cordon off the baggage check because one of the bags might have a bomb?

How do you make those announcements? And what if the PA system is down?

Most races have some limited procedures in place for a car/runner accident, or for someone dying on the course, but not for a mass catastrophe.

Do we, and be WE, the general race director community, need to come up with a standard play book for large marathons or even massive 5K's ?
While it seems sense to have individual races work out the details with individual venues and authorities,
there is a lot to be said for one set of rules that work for all events everywhere, so that we all know what to do in an instant.
Not just the race managers, but the team leaders everywhere should know the drill.

Then I ask, does it even make sense to even have a plan for big disasters, based on how rare the risk?

There again, I have often been quite disappointed at the response at small disasters on races of all sizes.

I have been at events where, to be honest, the response to a runner dying on the course or a car runner accident has just been to dial 911.
If some of the runners want to provide emergency assistance fine, but the race management basically did nothing more than wring their hands.
One of the arguments for calling 911 and doing next to nothing was to not be liable, don't want them to sue us.

It would be good if more races had standard procedures, and more race / club insurance policies spelled out what we should and should not do.
We also need to know if the Good Samaritan laws in various states will protect us when rendering assistance.

By having national standards, that are propagated by clubs, large events, runners websites etc, we may have better coordinated responses.
It must help if runners know the plan and drill too. For many of them have the skill sets we need in an emergency.

If, for example, any fireman, medic or doctor who runs in a race has a special red (+) on their bib number, you would know to ask them for help,
and your medical tent security would know to let them in to assist during an emergency.

It is just that I don't think any race I have ever been involved with would have got it's act together that quickly.

I have seen finish line towers blown over, just as the first finishers are coming across, blocking the race so that #2 has to jump over the barricade.
I have seen micro bursts knock down runners. I have seen cars get on to courses and hit runners. I have seen people die while running.

One less amusing one was a night time 'corporate run' 5K with maybe 15,000 to 20,000 runners.
The guy died 100 foot short of the finish, and the rest of the runners just keeped coming, jumping over him and the first responders.

Mostly, when people get hurt the reaction from race management has been less than stellar.
At least my local running club always pays to have an ambulance come out on site, even for a 5K.
Most races consider it just another expense and do not.

Ok, musing and rant over.