The latest (but not recent) episode I remember is this vote from June 2016, when the US senate rejected restrictions on sale of weapons to people on the terror watch list.
These are people that the same government deems too dangerous to allow on planes, but apparently preventing them from acquiring weapons is "against freedom"? (or something along those lines?)
On a similar line, I remember that also legislation to prevent people with mental health issues to acquire guns was stopped.
Why is this? What in the US political culture makes it so difficult to approve this kind of legislation? Is it all based on the slippery slope "if they take them away from them, then they will take them away from me"?
Note: I am not interested in answers that only say "the republicans" here or "the democrats" there, both parties have stopped similar legislation:
But the Democratic-controlled Senate voted against legislation pushed by the president that would have expanded background checks for firearm purchases to gun shows and online sales.