I used to play the video game Star Wars: Rebellion. One time, a large rebel fleet attacked one of my planets that I was using as my base of operations for that sector. There was no way that the defense forces I had there could win so I only had a few options available. I could retreat and let the rebels take the planet and all its resources or I could fight and maybe lose the fleet and the planet.
What I chose to do was fight. Instead of trying to take out a few of the big capital ships, however, I sent all my forces against the transports and landing forces. I lost the fleet but managed to destroy the rebel invasion troops and preventing them from being able to conquer the planet. Even though it did take a pounding in subsequent bombardments.
This was a loss at the tactical level but a strategic victory as I prevented my opponent from achieving his goal.
For firearm rights, the confiscations of firearms during Katrina were similar. Tactically it was an immediate loss as citizens were stripped of their means of self-defense by gov't authorities. Strategically however, it turned into a success as it led to the Vitter Amendment federally, numerous states passing similar non-confiscation laws, a successful lawsuit by they SAF/NRA against the city and mayor, as well as a very positive PR effect for our side and making people like Josh Sugarmann eat crow.
For the last few years, gun ban groups like the Brady Campaign to Prevent Gun Ownership have been trying to claim Heller and now McDonald as 'Strategic Victories' under the guise that 'gun bans are off the table' and 'reasonable gun control will survive'. Yet we haven't seen dozens of states passing their endorsed measures nor federal legislation get passed w/ overwhelming majorities. We're seeing them grasping at straws and struggling to even get their pet bills heard.
In the face of this, we need to continue to make sure that our victories are substantial and that they continue to 'Advance to the rear'.