In an attempt to distract from an emerging debate over how much to strengthen gun laws, Newsweek and Daily Beast special correspondent Megan McArdle called for people, even children, to be trained to “gang rush” active shooters. The Department of Homeland Security, however, recommends that people evacuate or hide in response to an active shooter, and to take direct action only as a last resort and when your life is in “imminent” danger.

McArdle's essay on how to prevent mass shootings in the wake of the tragedy in Newton, Connecticut, begins with a libertarian defense of congressional inaction on gun issues, even sneering that it is “easy and satisfying to be for 'gun control' in the abstract, but we cannot pass gun control, in the abstract.” You might well have seen most of this essay after any mass shooting in recent decades.

McArdle is so resigned to any gun laws failing to prevent gun violence that she concludes that people should be encouraged to “gang rush” shooters rather than hide: 

I'd also like us to encourage people to gang rush shooters, rather than following their instincts to hide; if we drilled it into young people that the correct thing to do is for everyone to instantly run at the guy with the gun, these sorts of mass shootings would be less deadly, because even a guy with a very powerful weapon can be brought down by 8-12 unarmed bodies piling on him at once. Would it work? Would people do it? I have no idea; all I can say is that both these things would be more effective than banning rifles with pistol grips.

So, in sum: the chances of achieving anything with any gun legislation are so low that in these circumstances, people should resign themselves to probable death by running at the person firing a gun in the hope that enough people will follow that their likely death will not be in vain. 

As Jonathan Chait points out at NY Magazine, this is an absurd proposition: 

Are you kidding me? You think gun control is impractical, so your plan is to turn the entire national population, including young children, into a standby suicide squad? Through private initiative, of course. It's way more feasible than gun control!

...

Unless I am missing a very subtle parody of libertarianism, McArdle's plan to teach children to launch banzai charges against mass murderers is the single worst solution to any problem I have ever seen offered in a major publication. Newsweek, I award this essay no points, and may God have mercy on your soul.

Moreover, the Department of Homeland Security has specific guidelines on how to act when one's life is threatened in a shooting situation. Objective 1 is to evacuate, and if you cannot evacuate, objective 2 is find a hiding place: “If evacuation is not possible, find a place to hide where the active shooter is less likely to find you.” DHS recommends that people take action against an active shooter only as a last resort and when your life is in imminent danger. 

From the DHS manual: