U.S.-China relations solve extinction---effective engagement solves Arctic conflict, climate change and North Korea war.

Washington needs to bend the arc of the relationship between the two most important geopolitical actors of the 21st century, but had better be careful not to break it altogether. That is a significant risk, especially in an election year in the highly polarized U.S. Bottom line: America should confront China where it must over crucial policy issues — but at the same time seek zones of cooperation wherever it can. One possible area of cooperation may seem odd, but offers a real chance to work together: the Arctic. China, despite lacking actual shoreline there, has been interested in what sailors call the High North. Beijing has been granted observer status in the and has been active in maritime operations, largely in concert with Russia. It is , establishing a satellite ground station and a broader research facility. China is also building a 30,000-ton , comparable to the largest Russian vessels. The Chinese are mostly interested in exploiting minerals, oil, gas and commercial shipping routes. But there may be room to cooperate, and some initial Arctic confidence-building measures the U.S. could explore include joint search-and-rescue exercises, scientific research and protocols for ship and aircraft proximity (which could later be applied in the South China Sea if they were successful in the Arctic). A second obvious place to work together is in controlling Kim Jung Un of North Korea. Neither the U.S. nor China has any interest in permitting Kim to further expand his nuclear arsenal (especially the U.S., given its allies in East Asia). For China, a war between the U.S. and North Korea would be a disaster — Kim would lose, and waves of refugees would flow across the China-North Korea border. Working together, the U.S. and China could put irresistible economic, diplomatic and military pressure on North Korea to cease provocative actions and control its small but significant nuclear capability. True, no approach has worked with North Korea thus far. Trump's "personal diplomacy," President Barack Obama's "strategic patience," and President George W. Bush's stick-over-carrot approach did not slow the growth of the nuclear arsenal and the ballistic missiles. In the end, it seems, all roads to Pyongyang run through Beijing. Another potential zone of cooperation is the environment. The U.S. and China, as the two largest economies in the world, both have a vested interest and fundamental responsibility in ameliorating the degrading global climate. And they found when Obama was president. Step one in building a zone of cooperation here is for the U.S. to re-enter the Paris climate accords, something the Trump administration has adamantly opposed. Fortunately, Joe Biden has pledged that should he win election, the U.S. would rejoin the pact.