South Korea and Japan just don't get along. That's a problem for Biden

In uniting Western democracies against Russia's invasion of Ukraine, United States President Joe Biden managed something his critics thought was impossible. Before Moscow's unprovoked war, European nations were split over issues ranging from Russian energy pipelines to Brexit and -- with lingering resentments dating back to Trump-era trade disputes and the Iraq war -- some even appeared to be rethinking their relationship with Washington.

Yet just three months on and -- as shown by Finland and Sweden's eagerness to join NATO -- Biden can say with some justification that the West is "stronger and more united than it's ever been." Now, as he flies into Asia for his first trip as President, Biden faces a similarly daunting task in uniting two Asian democracies: South Korea and Japan.

The two countries are Biden's strongest allies in the region -- together they are home to more than 80,000 American troops -- and the US sees both as vital to building a coalition of like-minded countries to combat two threats potentially even more threatening to world peace than Russia's invasion: the rise of China and North Korea's nuclear program.

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