Obama, like any other President, does not have the authority to make some touch-ups on the second amendment, or any other amendment for that matter. The Constitution (not the President) is the supreme law of the land, and cannot be changed outside of the amendment process.
The first 3 words of the United States Constitution... We the people. IN BIG BOLD LETTERS. There is a reason for that. Don't EVER EVER forget why.
There's no reason to have a constitution, and a dictatorship wouldn't be such a bad thing. <iframe width="640" height="360" src="http://www.youtube.com/embed/gQourq7M8R0?feature=player_detailpage" frameborder="0" allowfullscreen></iframe>