I think we have gotten to the point that we are just comparing bombings with shootings, but that really isn't the point. Picking a gun and shooting someone is easier than making a bomb and blowing someone up, sure. But the point is, in the absence of guns, we humans will find a way to kill each other, one on one or en masse. Bombs are just one way of doing it, and while may think they are hard to make, they aren't.
But it doesn't have to be bombs; I can go to any home improvement store or supermarket and for about $50 come out with what I need to make an agent that will severely harm or kill many people.
And whether is guns, bombs, gasses, sabotage, or a hammer to the head, the more we use deadly agents, the better we get at it.
Now, don't get me wrong; I am all for well regulated firearms, they should be, and I do think there are some loop holes that need to be closed. And while "less guns, less shootings" may seem logical... but honestly looking at the evidence and where we are as a society, I don't know if that actually holds water. People will point out to rates of shootings in other countries were guns are highly restricted or even banned, without consideration to those societies and cultures, and what they have endured on their soil.