If you're not a Christian you don't have any idea how to discern or keep scripture in context. Even some supposed Christian don't put scripture in context either. It's all about keeping what Jesus said in it's correct context.
Jesus' sermon on the mount was given to his people who were brethren. Yes, there are situations when one should turn the other cheek. However, he said to turn the other cheek. He didn't say let them kill you.
Yes, he came to give his life the first time( for our salvation), but when he comes back (soon) he will use a two-edge sword and destroy the wicked.
Scripture says, Jesus told his disciples not to carry a sword when they went among their own brethren in traveling and preaching the gospel. However, afterwards Jesus told them to sell what they have and to buy a sword (for their own physical protection) when they were sent to all other nations to preach the gospel; because they were going to be traveling among gentile nations where they may come across robbers, and other criminals.
The right to bear weapons (guns, or whatever) to protect ourselves and our families is a right from God Almighty to every last one of us The government didn't give that right so they can't take it away. .