I'm all for back ground checks and "red flag" warnings...most folks are...but that would not change the constitution.
Congress passes laws all the time. The Supreme's decide if they're constitutional. Back ground checks are. Depending on how far the "red flag" warnings go will determine their constitutionality.
How does Congress pass civility and morality laws? In the end, that's all this comes down to. Assault rifles account for around 1% of gun deaths....
The inner city is a war zone and a homeless encampment, opioids are out of control, depression in young adults is at record highs, the deficit continues unchecked and the beat goes on.....
1%? You don't say.