I think a large number of people against firearms fail to understand history. Our forefathers understood the meaning of Tyranny. They were being oppressed by a government, and left with little recourse other than to revolt. This situation has repeated itself many times throughout history and across the globe, so this was hardly the first time the need existed, nor will it be the last.
The purpose of the second amendment is to ensure that should we have the need to revolt against a tyrannical government at any point during the future, we will have the means to do so. Owning firearms isn't about the ability to go out and hunt. It isn't about simply having the freedom to own firearms. If you read the statements by the founders of this nation, it is very clear that the second amendment is about having the tools necessary to ensure the safety of yourself, and your loved ones.
It is folly to think that anyone else is responsible for your safety. While there may be those that take up that responsibility, there are far less of these sorts of people than there are citizens. It is physically impossible to protect everyone simultaneously. Disarmament is not only shirking your responsibility to yourself and your loved ones, but it enables the very sort of thing we fought against when founding this nation.
It is critical that the right to defend oneself not be infringed, as a tyrannical government will not defend you, but rather will be on the offensive.
While safety is a huge concern and should not be ignored, all too often we forget our own history. We can't forget where we came from, nor a global cycle of tyrants rising and terrorizing their own citizens. History repeats itself, and those who fail to recognize this fact are doomed to repeat it.