The US has a lower murder rate than all but a handful of countries in the Western Hemisphere, which would be:
Martinique, Canada, Chile, and Argentina.
Countries in the Western Hemisphere with higher murder rates (and almost invariably much tighter gun laws) would include:
Greenland, Venezuela, Uruguay, Suriname, Peru, Paraguay, Guyana, French Guina, Equador, Columbia, Brazil, Bolivia, Bermuda, Panama, Nicaragua, Mexico, Honduras, El Salvador, Belize, Costa Rica, the US Virgin Islands, Cuba, Trinidad, Montserrat, Jaimaca, Guadelupe, Haiti, Grenada, Dominica, the Dominican Republic, St Lucia, St Kitts, St Vincent, the Caymans, Barbados, Antigua, Anguilla, and the British Virgin Islands.
We also have a lower homicide rate than Russia, the Ukraine, Moldova, and several other states in Eastern Europe, and also lower than some of the Baltic states. Of the contries in Western, Northern, and Southern Europe, most have looser restrictions than Connecticut, Maryland, Chicago, or New York, and some have looser restrictions than our gun friendly states. In Switzerland, assault rifles are commonly found in bedroom closests.
US states that demographically look like Europe also have Europe's low homicide rates, or lower, even though they have staggeringly high gun possession rates, like Montana, the Dakotas, Iowa, Oregon, and Vermont, all of which are way more armed than Texas. If you punch US gun possession rates and homicide rates by state into a spreadsheet and plot it, you don't get a line, you get a random scatter and Louisianna. Hawaii and Rhode Island have very few guns and low homicides, Montana and many others have lots of guns and have very low homicides, virtually identical to Switzerland or Austria.
I don't think you're fools. I know you are. Cops and gun owners have spent the last week thinking they're arguing with five-year old girls.
A) You're never going to get any meaningful legislation passed, because Democrats long gave up on gun control because it was costing them key demographics that they need to win, like blue collar union voters.
B) The legislation you tried in the past not only made guns much better, but vastly increased sales.
C) The restriction put in place on large capacity magazines resulted in the sale of roughly one hundred million extra large capacity magazines. They're disposable, so we stocked up. Now we have about a centuries worth on hand. We only have tens of billions of bullets.
D) The Supreme Court has ruled that Americans have the Constitutional right to carry useful, commonly owned arms in a working state, without any onerous provisions or costs. That overturned even existing gun bans in cities like DC and Chicago, and will apply to the states, as well. Legal scholars have already weighed in on this.
And even if you did manage to amend the Constitution, pass a ban, get cops to even try to enforce it (cops often refuse to take really good guns at buy backs), and then somehow convince gun owners to go along with it, we'll still have higher murder rates than Western Europe, possibly much, much higher than present.