Mines in the US are frequently delayed or prevented from opening entirely due to environmental lobbying pushback. We've got plenty of resources we could be tapping into, but cheap overseas competition plus strict pollution controls and environmental lobbying red tape on top of that makes it a very long, expensive investment to see a return on.

For example, the Interior Department instated a 20-year moratorium on renewing any leases for mining operations near the boundary waters in northern Minnesota. Understandably, the consequences of copper sulfide ore polluting the waters is severe, but the 20 year ban is nonsensical. The dangers won't be any less in 20 years. We aren't exactly 20 years away from magical technology that will make it safe. It's a purely arbitrary number meant to appease environmental groups without having to pay out to buy the land and permanently ban resource extraction.

For what it's worth, I'm not really in favor of the mines, per se, just irked that we keep playing games. Either do environmental reviews and let miners mine when they have leases to do so and appropriate safeguards in place, or don't. A 20 year moratorium just sets up political groups (mining and environmental lobbies) to suck up more cash donations and sets up another political fight down the road.