At the national level I believe the problem is slightly easier (though still extremely difficult). We generally have effective national institutions, so we "just" have to convince the populace that the pain is worth the gain. It's easier to stomach a little bit of pain for the common good as long as people believe that everybody else is also doing their part.
Here's a solution at the international level: https://issues.org/climate-clubs-to-overcome-free-riding/
At the national level I believe the problem is slightly easier (though still extremely difficult). We generally have effective national institutions, so we "just" have to convince the populace that the pain is worth the gain. It's easier to stomach a little bit of pain for the common good as long as people believe that everybody else is also doing their part.