President Donald Trump, most of the Republicans in Congress and the National Rifle Association are culpable in the mass shootings and killings that have been occurring recently.
This country is way overdue for having an appropriate, strong, enforceable federal law against ownership and/or possession of military-style rifles and all weapons of mass destruction.
Reliable background checks must be required for all sales and transfers of guns, including private actions, excepting very small-caliber handguns. Anyone selling or transferring guns without the appropriate background check should be held liable if the weapon is used illegally.
These requirements and laws do not obstruct the basic principles of the Second Amendment. Times have greatly changed since that amendment was ratified; these weapons of mass destruction and mass shootings did not exist in 1791.
Also, the FBI, police and general public must be more vigilant in monitoring and reporting potentially threatening activity, including websites.