There are two reasons:
First: America is not a "Democracy"; it's a Republic
Second: The Constitution of the United States acknowledges (and guarantees) the right of Americans to "Keep and Bear Arms".
Why Obama is powerless to reform gun laws - BBC News:
October 04, 2015: Can't the states do their own thing? In the Senate - which currently has 54 Republicans and 46 Democrats (or Democratic-supporting independents) - the individual state populations are the key. The votes of Senators John Barrasso and Mike Enzi in pro-gun Wyoming (population 584,153) have the same weight as gun-control-backing Senators Dianne Feinstein and Barbara Boxer in California (population 38.8 million).Yeah, that's the "Republic" thingie.
As Thomas Jefferson said, "Democracy is nothing more than Rule By Mob"; and today Liberals Americans are 'the mob'.
Our "Democratic" president would dearly love to impose his bias upon free Americans. It's a source of irritation to our Dear Leader that he cannot arbitrarily impose draconian restrictions on our freedoms.
Don't think that a lot of Congressmen wouldn't back him in this raid on Constitutional Rights, but the folks who started this experiment in liberty were smarter than the Brits, and Obama combined. Which wasn't much of a challenge, as it turns out.
(Curious, that the "Constitutional Law Professor" who rules America today doesn't seem to 'get it'.)
(Go here for a discussion about the Electoral College)
If you're not confused, you were not paying attention. The "Electoral College" concept is confusing to 99.9% of Americans (including me). But one would be surprised if an American President who is also self-identifying himself as a "Constitutional Professor" didn't understand it.Obama cannot impose arbitrary restrictions on Firearms Ownership (or in other words " .. is powerless to reform gun laws ...") because he's not a King. He cannot rule by fiat. He needs the support of BOTH houses of legislature, and he can't get it because those senators and representatives are dependent upon the good will of their electorate to get themselves re-elected next year. Without the firm support of the Electorate (you and I),
And as Al Gore learned a few years ago, one of the EASIEST ways to lose an election is to infringe on the Constitutional Rights of the American Citizen.
Even if you're a Rabid Anti-gun Liberal, you don't want to seriously propose a Constitutional Amendment unless there is first a Constitutional Convention to support your ever-so-popular view. And even then, it's still not a good idea because then there are "other issues" which might come arise, and you are likely to lose more than you might have gained.
ONE OTHER QUESTION:
We understand why Americans would want to ask this question.
But why is the BBC (British Broadcasting Corporation) involving themselves in this "purely American" issue?
It may be a matter of Schadenfreude;
They're so gleeful about their firearms-ban that they cannot bear to let American Freedoms demonstrate that their 'Violence" issues haven't been resolved by their draconian Gun Control measures (which are, by the way, not working!).
So they are violently (excuse the expression, NSFW in Britain) opposed to any other country which might be willing to accept a degree of 'gun violence' in protection of "Personal Freedoms" .. thus allowing private citizens to defend themselves in their homes and in their persons. Because if they let THAT example go without criticism, they might find themselves defending the logic in exposing their citizens to violence without allowing' them the means to defend themselves, their property, and their family.
That would be embarrassing.