No, it wasn't. That's bullshit the Republicans made up to justify it still applying. It's about defending the nation from attackers. At the time of writing, militias were the common way militaries were formed for most nations. Only the most prosperous had standing professional armies. The brand new US was not expecting this, so militias were seen as the only way to defend itself. This is no longer true, so the second amendment, which bases itself on this premise, is not valid.

A well regulated Militia, being necessary to the security of a free State, the right of the people to keep and bear Arms, shall not be infringed.

I still defend people having the right to own firearms, but I also support restrictions. People should have to be trained in it's safe operation, maintenance, and storage, for example. They should also have to prove they have a safe place to store it. There are a lot of ways we can still protect people and allow for firearm ownership and usage.