Slovakia, now excluded from NATO, signs a mutual defense pact with Russia and Russian troops deploy into Slovakia. The United States has substantial investments in Central Asia. Russian troops linked with pro-Russian elements move to reintegrate the region with Russia, threatening U.S. investments. Russia and China, now allied, begin providing North Korea with military technology intended to tie down U.S. forces in the region and suck additional forces into the Northwest Pacific. China begins a campaign to harass shipping in and out of Taiwan, using air and naval forces to sink or seize Taiwanese ships.
China follows Russia into internal disintegration.
Western investments in the coastal region, as well as westerners, are in danger. This is a sampling of the issues that might confront the United States over the upcoming years, or even months. The potential areas of engagement range throughout Eurasia. The locations of crises are not only unpredictable, but depend partly on internal decision making in Moscow or Beijing. In some scenarios, the threat doesn't arise from decision making at all but from its break down.