If this turns out to be terrorism related, regardless of whether "lone wolves" or if ISIS or other groups take credit, personally I think it will hurt Obama et als cries for gun control.
When it's a whacked out white guy it's a different story, but when the MSM has already been covering potential terror attacks over the holidays, this may actually get some fence sitters thinking about, "This could happen around me. I might want to protect myself". I think more of the general population are able to grok that if it's terrorists, they might not be getting their guns from the local gun store.
Maybe, anyway.