I spoke about this earlier. From the beginning solutions were not necessarily all or nothing. For example, why should a firearm intended for home protection be small and light weight? In addition, current technology and science, could make a huge difference here. For example, firearms could be made or altered so that, with the use of satellite and/or a remote control technology, are operable only within a specific limited locality or make a warning sound and visual signal out of those localities. Or at least they can be made trackable by satellite so that appropriate devices installed at public or gathering areas like supermarkets, schools, churches, movie theaters and the like can detect them. 

But nothing of that can be done unless people are released from the bondage of the so so long ago expired second amendment.