From the US perspective, SE Asia's population demographics make economic access a key determinant of the future. If China can credibly restrict shipping in the

From the US perspective, SE Asia's population demographics make economic access a key determinant of the future. If China can credibly restrict shipping in the south of the South China sea, then that accrues substantial economic power in the coming decades. Which is another way of saying that if Malaysia, Indonesia, and the Philippines don't believe in the US's regional power projection, they'll allow China to do as it wants. In any escalation scenario, Guam gets plastered. Taiwan is blockaded. Okinawa is... well, that's a wildcard. But Australia has land. A LOT of land. So establishing closer military ties (also with the Philippines) affords freedom of dispersement. Which in turn increases US retaliatory options in the case of escalation. Which makes sudden escalation less likely, as China has less to gain from it. Or, in other words, the Pacific is now Europe ~1960, with the US trying to establish a credible capability to surge into the region in the event of hostilities.