I have been bothered by the Hitler/Gun Control comparisons being made, so I did some digging.
Today, there are somewhere between 60 and 80 million gun owners out of a total of 350 million people in the United States The contiguous area of the lower 48 United States is just short of 3 million square miles.
In the 1930s, when Hitler was in charge, Germany had a total population of 60 million.  Germany’s area is 137,000 square miles, approximately the size of Minnesota and Iowa combined.
I would like to consider two things.
First, on a political level, gun owners make up a huge voting bloc; just consider those numbers above.  Even if you discount the coordinated influence of the ‘special interest group’ known as the National Rifle Association, that is one huge voting bloc.  Can we honestly see laws passing that would totally ban guns?  I believe our federal legislators, as much as they are accused of being out of touch, wouldn’t miss that voting power.  I think they are aware enough to know what their constituents want and don’t want.  They wouldn’t pass a law banning all guns any more than they would pass a law against any other large bloc of voters.
Has Obama overstepped his bounds with executive orders?  I understand the trepidation people have about such a step, but even when it comes to executive orders, our presidents have used it quite widely – a total of 13,632 over the years, to be specific.  (http://www.archives.gov/federal-register/executive-orders/disposition.html)  Obama has used 166 so far.  Bush II used 290.  Clinton numbered 363.  Mr. Reagan, 380.  Going further back, Nixon had 345, which would have included a few regarding Watergate and that whole mess.  Truman signed 893, some of which were struck down by the Supreme Court.  FDR, serving for around 15 years, leads the whole pack with 3,466 – some of those during the tough times known as the Great Depression.  Despite his own opinions, Obama is leaving any specific banning up to the congress – and the previous paragraph already addresses the unlikelihood of them passing anything even close to a full-out gun take away.  I suspect he could have banned guns via executive order. Even considering he’s a second term lame duck president, he needs to consider that same voting bloc of both gun owners and those who own no guns. He would be foolish to think that he can roll out an executive order that strongly favors either side of the issue at the risk of extreme displeasure of the public, and even impeachment from one side of the congress or the other.
Remember, too, that our government has checks and balances.  As already stated, the Supreme Court has struck down some of those executive orders over the years.  Our congress can – and has – called for impeachment over various issues.  Watergate was probably the worst in my lifetime, but then there was the Clinton stuff, too.  And of course, to me, the ultimate in checks and balances of our country, our voting populace.
In Hitler’s Germany, there was so little to temper him – so little to fight back.  If there were any checks and balances at all, they were inoperative.  The voting populace wasn’t near as aware nor as educated (I think) as what we have now in the United States.  There just seems no way that any American president has had at his disposal the same kind of dictatorial power as Hitler.
Secondly, there’s the logistics of it all, and why I started with the geography lesson. Hitler had a land area of five percent of the United States to cover in order to enforce his plan.  He had an army to do it.  He tried to do what he tried to do, but ultimately, he didn’t get away with it, as you well know.
So then there’s this, my friends.  Even if our federal decision makers – president, congress and Supreme Court – come up with a law to totally remove all guns from all Americans, can you imagine the unenforceable nature of such a law?  How in the name of George Washington do you cover nearly 3 million square miles, removing guns from 60 to 80 million citizens?  How would YOU do it?  Can you see ANY WAY at all in which such a law could be implemented?  Would the law enforcement officers be directed to do so?  The National Guard?  It just seems so virtually unenforceable to be ridiculous to consider.  Knowing that, what would be the advantage of passing such a law?
My conclusion: Relax, everyone.  I trust our system, as warped and dysfunctional as it may be.  Leave the Hitlerisms out of it. Such comparisons to the Führer are rooted in fear. – Let us intelligently, prudently, and practically pass any regulations that need to be passed.  Yes, some government will be challenged, (and should be) and some will be well done…. And that is the sign of a living, thinking citizenry.