Two things that come to mind.
1. Imagine if we could be at the forefront of technology to help the world, we have a lot of smart people who end up taken up by overseas institutions. Imagine if we supported them here.
2. I recently thought of drugs. Why bother trying to catch people importing or making drugs. It's the same argument. They never seems to make a difference when they catch someone and there is always someone else to fill up the gap in production but they spend millions trying to catch them anyway. So if we could use the same drive for climate change we might make a difference for everyone.