I've seen the "What would Jesus do?" question asked in relation to gun control. I'm not sure if that is a fair question to ask.
No, I'm not stepping away one bit from having Him as our ultimate role model (as well as Lord and Savior), but Jesus, lest we forget, was and is God and has the ability to mold reality to His liking. Were someone to come after Him with an AK-47 or Luger, He could turn to the shooter and say "that's not a good idea" and the shooter would stand down since Jesus could freeze him in his tracks.
We don't have quite that power over a determined shooter, although we had one case earlier this month where a teacher talked a shooter down.
Noting that such rhetorical power isn't a universal panacea, is self-defense allowed at all, given the turn-the-other-cheek command of Jesus? Luke 3:14 is one tangential way of looking at that issue-
Then some soldiers asked him, “And what should we do?”
He replied, “Don’t extort money and don’t accuse people falsely—be content with your pay.”
Jesus' command wasn't "get your stinkin' butt out of the Army and apply for conscientious objector status." It was just to be honest and not to abuse their authority. Were violence a total no-no, He'd be railing against the state use of power.
Thus, violence in a greater cause might well be justified, especially when we saw Israel take things by force when called upon in the OT; Jesus as part of God implicitly signed off on that violence as well, or at least his minority opinion after being overruled by his Dad and the Holy Spirit wasn't noted in the Trinitarian Record.
That makes state violence called for on occasion. Is personal self-defense called for?
"Turn the other cheek" leans us towards walking away from a fight where possible. A slap from a disgruntled person might be the extent of violence, and responding by starting a brawl might not be the best response, since it may solve little other than to create bruises and broken bones.
However, it is a bit of a stretch to see where armed folks raping and pillaging through a neighborhood has only diplomacy to stop them. Diplomacy is the first response when possible, but self-defense would be called for at some point if the offending party is not responding to reasoned dialog.
They didn't have guns in Biblical days, but they did have swords. Luke 22:38 showed up when I did a search on "Sword"
The disciples said, “See, Lord, here are two swords.”
“That is enough,” he replied.
Jesus didn't tell them to leave swords behind or turn them into plowshares, but that two swords was enough for what they were doing.
[Update 445PM-The old Junkyard Blogger, Bryan Preston, noted that I missed the verse before-"if you don’t have a sword, sell your cloak and buy one." Big oops. Not only do we have swords allowed, but a must-carry rule was in force.]
If the disciples were allowed to pack steel back then, packing heat today seems OK if called for. That would be something left to the modern disciple to figure out, if the situation called for having it around.
Jesus didn't pack heat, but He had the disciples packing the first-century equivilent.