Yes I believe that guns trigger violence. Youth who gets hold of the guns in their hand may end up using it. There are lots of factor to keep in mind thats causing violence. From watching movies and video games kids pretend to become like the characters in the movies and if they come across weapons they tend to use them.
There is no reason to believe that guns trigger violence. People that have a tendency to be violent will exhibit those tendency with or without firearms. Gun violence will exist as long as guns exist because there is no 100% sure fire way to guarantee that only the right people will be able to obtain those firearms.