Earlier quoted context omitted.
Or laws/taxes are passed, which incorporate the externalities, and subventions for detrimental efforts are cut. That is "just" a matter of political will.
How much war are you willing to wage to force other countries to do the same? I think that's really the only question that matters when it comes to the "everybody pass laws" plan.
If all countries, that are supposedly interested in being the best climate change affectors, all competed to truly be the best - we'd be in a far better spot. The war you allude to is not international in nature. It's national. If the US, for example, actually removed campaign contributions and lobbying allowances from organizations responsible for a majority of annual pollution we'd already be down the road. But instead it is national politics, and those legislators, that are the real roadblock to starting the snowball move towards clean technology.