In theory, I've always envisioned our Forefathers's primary intent of the 2nd Amendment as a way for citizens to keep the government in check. This is no longer practical given the disproportionate balance of power between citizens and the government. Citizens, at most, have semi-automatic assault rifles whereas the government has tanks, bombs, planes, weapons of mass destruction, etc.
In practice, I see a more likely purpose for the 2nd Amendment would be if the country, state, or city moves to lockdown and law enforcement can't respond to crimes.
This thought comes to mind after a friend, originally from another country, asked me about what lockdown could like as she voiced her concerns of being alone if movement was prohibited.