more than 15 big American companies cut ties with the national rifle association.

This is the big gun lobby group that has long been seen as the absolute obstacle to any kind of meaningful gun control in America.

The companies' decided that they no longer want to offer discounts or affiliated credit cards to NRA members,

which is a big shift, and it reflects the huge consumer pressure that they're feeling through social media.

Most of these decisions to cut ties by say Hertz and Delta Airlines are largely symbolic.

So they are certainly not changing anything about the way guns are sold in America.

But they may be changing perception about whether the NRA is an unstoppable force.

The big ways you could deal with the huge influx of guns in the US are two:

One is by going after the gun manufactures, but they're pretty small companies, and it's relatively hard to go after them.

The more obvious way is by making it harder or less attractive for retailers and payment processors to participate in gun sales.

Right now, Paypal does not allow you to buy firearms through their website.

In theory, the big banks and VISA and Mastercard could do the same thing,

and that would make it much harder for someone who wants to run to the store and pick up a bunch of guns.

Similarly, if big retailers, such as Cabela's, the big sports equipment store, decided to stop stocking semi-automatics.

Again it would be much harder for people to get them, and it might slow down the flood of violence that we've been experiencing.

What really needs to happen if the US is to address its gun violence problem is probably a change in the law.

Making it harder for people to buy guns, making some guns less available.

And so far the NRA has been an unstoppable political force.

The question will be:

the fact that these companies are now getting involved,

and in social media pressure in the wake of the parkland shooting, is putting the weight on the other side,

whether that would finally lead to the kinds of law changes that the US probably needs?