Pure emotionalism and politics, devoid of any statistical evidence that stricter gun control laws have ever lowered gun crime. And in the face of statistical evidence that the worst gun crime exists where it is most difficult for law abiding citizens to own guns.
Armed robberies and home invasions increased since Britain and Australia banned private gun ownership. Chicago defeats any idea that gun bans keep guns out of the hands of criminals.
There were and are reasonable ways to keep legitimately suspected terrorists from buying guns, but the Constitution requires that citizens have access to due process concerning their inclusion on the Watch List. Democrats oppose that due process; better to have the issue than the reform.