Not over firearms, there will be a quiet defiance and complete lack of effort to enforce it (Partly out of defiance and partly out of self-preservation) in the vast majority of the US...like the NJ assault weapons ban in the 90s, there was no effort to round up any weapons, they just wrote an additional charge if they happened to find any on you or your property, if you were arrested or even if the cops came in to check on someone for innocent reasons. Of course their 'Assault weapons' and 'gun' crime stats went up, a third of the violations after passage being simple possession.
The thing that WILL cause a shooting war is when the entitlement system finally breaks, we are years away from that although we are starting to circle the drain. A lot of people will wish they had near-military weapons then, which is one of the reason Our Friends in Washington want to get rid of them now. Any urban liberals who crop up out here in the scorned boondocks looking for refuge when that day comes will be barking up the wrong tree entirely.