I’ve been expecting just that for the last few decades. With the advent of those willing to engage by way of suicide bombings, both vehicular and while afoot, coupled with small arms, the likelihood has only increased.
I open and concealed carry depending on my mood and the locations visited. But I am never unarmed despite the inadequacy of the arms I carry. I keep a rifle or shotgun in my vehicle as well. One never knows when those weapons might be needed. Hopefully the need will never arise.
I’m sure when this happens in America it will encourage more people to carry to the mall and everywhere else!