"Ineffectiveness"?
Gun Control is fairly effective at the real intended goal around the world. To keep whoever is in power, comes to power, or seizes power facing limited physical opposition from the people.
When only a military loyal to a tyrant, and a police force loyal to a tyrant have guns, then 50,000 armed people can control 500,000 unarmed people even if the unarmed people don't agree.
If you take the rulers of every single nation, and combine them into a single voice, you will find they have absolutely no problem agreeing that those they rule over should be disarmed (at least of any arms even moderately capable of resistance.)
So it should come as no surprise that something like the UN is strongly against firearms (except those possessed by governments, or old relics used by hunters.)
The official reasons for support and passage of legislation may be different. It may be some highlighted single incident or massacre. The real reason however is control. Throughout history all rulers have sought to disarm those they rule over from any form of effective resistance.
How else can thier thousands of armed officials rule over millions if thier is a disagreement?
From the banning of crossbows that could be used by a simple peasant to penetrate the armor of the elite noble's Knights. Knights who were trained by the elite to be capable of defeating any peasant since boyhood.
To the modern banning of handgun rounds that through design can defeat body armor worn by all government enforcers.
The purpose is the same. To insure the few remain in control of the many as easily as possible.
What was the quote?
The most foolish mistake we could possibly make would be to permit the conquered Eastern peoples to have arms. History teaches that all conquerors who have allowed their subject races to carry arms have prepared their own downfall by doing so.
-Adolph Hitler
You can substitute "subject races" with "peasants", "serfs", or other terms to describe those who are ruled over and the quote is the same.
Governments know that people who possess effective arms are harder to rule over. Because in the end the only power they have to fall back on, is the power to send in armed men to crush resistance. A power not as mighty against well armed subjects.
If that means governments have to appear to be doing the will of those "in favor of common sense legislation" then that is what they will say as they sign restrictions into law.
So arms control is quite "effective", and has been for millennia.
Which is the very reason the founders of the Constitution wanted every citizen to have arms on par with the national government, every locality to have militias, and every state to have such forces. So every single portion of the United States could stand strong against any other portion that tried to impose it's will.
So no government, foreign or domestic could enslave the free people of the United States.
Before a standing army can rule, the people must be disarmed; as they are in almost every kingdom in Europe. The supreme power in America cannot enforce unjust laws by the sword; because the whole body of the people are armed, and constitute a force superior to any band of regular troops that can be, on any pretense, raised in the United States. A military force, at the command of Congress, can execute no laws, but such as the people perceive to be just and constitutional; for they will possess the power, and jealousy will instantly inspire the inclination, to resist the execution of a law which appears to them unjust and oppressive.
- Noah Webster
Gradual loss of gun rights to achieve the goal of disarmament is also not a new idea:
When the resolution of enslaving America was formed in Great Britain, the British Parliament was advised by an artful man, who was governor of Pennsylvania, to disarm the people; that it was the best and most effectual way to enslave them; but that they should not do it openly, but weaken them, and let them sink gradually...
-George Mason
