Conservative commentator Dan Smoot went on this rhetorical tirade after the assassination of President John F. Kennedy in 1963: https://www.youtube.com/watch?v=3zJOnMRURmY
President Lyndon B. Johnson in 1968 on gun control legislation passed in the wake of the murders of Rev. Martin Luther King, Jr. and Robert F. Kennedy:
From the NBC News Archive description on YouTube:
The president said at the time "AS BIG AS THIS BILL IS, STILL FALLS SHORT BECAUSE WE JUST COULD NOT GET THE CONGRESS TO CARRY OUT THE REQUEST WE MADE OF THEM. I ASKED FOR THE NATIONAL REGISTRATION OF ALL GUNS AND THE LICENSES OF THOSE WHO CARRY THOSE GUNS.FOR THE FACT OF LIFE IS THAT THERE ARE OVER 160 MILLION GUNS IN THIS COUNTRY; MORE FIREARMS THAN FAMILIES. AND IF GUNS ARE TO BE KEPT OUT OF THE HANDS OF THE CRIMINAL; & OUT OF THE HANDS OF THE INSANE; & OUT OF THE HANDS OF THE IRRESPONSIBLE; THEN WE MUST JUST HAVE LICENSING"