The Left really does not like the Second Amendment.  I am not sure why this is? Maybe because it was designed to protect the American people from the American government. We see in the Federalist papers the importance of limiting the government. [The 2nd amendment was made as a limit on government.] I think since the Left sees government as the greatest good, and people as worthless, thus the 2nd Amendment must bother them.

I wanted to mention that I think limited government was foremost in the minds of the founding fathers as the sole way to guarantee freedom. 
They must have taken note that Sparta considered themselves free even though they were not a democracy. {See Herodotus the discussion between Xerxes and the exiled king of Sparta who warned Xerxes what kind of men he was about to encounter at Therma. 1.7 million men against 300 Spartans was simply no match. According to the exiled king of  Sparta, the reason was because the Spartans considered themselves free and would guard that freedom at all cost. And this freedom was not because of loyalty to Sparta, but loyalty to the Law. And the Law required only one thing. Never retreat.} The reason is the government was limited by the fact that each of the two kings and the Ephors limited the power of the other.

1.7 million against each Spartan was 5,670 men against one Spartan.