Chemicals don't care about borders.
A business may only pay taxes to one country, but the pollution it makes doesn't care about national borders. See for yourself: NASA created an animation showing how the wind moves pollution particles around the world.
The white wisps represent smaller particles that generally come from burning crops and industry. These particles get into people's lungs, causing heart attacks, cancer, respiratory diseases and other problems. (The red wisps represent big particles, like sand, which aren't nearly as worrying.)
"Particulate matter is a really really serious concern," explained Gina McCarthy, the former EPA administrator and director of the Center for Climate, Health, and the Global Environment at Harvard. "It really wasn’t intended to be breathed in."
The message is as hopeful as it is daunting: we can't pretend pollution from afar isn't hurting us, and we can't pretend our pollution isn't hurting others. The world needs to work together to solve this particular problem — there's just no way to do it individually.
A friend once told me that the best way to deal with pollution is to privatize all land. That way, landowners have an incentive to protect their land. This problem with this theory is that pollution doesn't care who owns what land. When you pollute the air, you don't just affect the houses near the pollution site. The pollution dumped in that air can travel across the country or even the globe. Landowners near the pollution site only have to deal with a fraction of the pollution they cause.
"Pollution really doesn’t know boundaries," McCarthy told me.
Chemicals don't care about borders.