Taiwan is a potential trigger point for a world war should China invade it, as Russia has invaded Ukraine.
Taiwan produces nearly all the most advanced chips that underpin the most advanced economies and their defence capability.
Maintaining a democratic Taiwan facilitates the long term strength of the liberal democratic rules based world order. It is also important in maintaining the free navigation waterways that lead to Japan and South Korea as well as the nations of South Asia and Pacific.
It is a significant player in the combined intellectual and economic resources of the democracies that are needed to manage authoritarian China global ambitions to alter the existing world order.
Taiwan, Japan and South Korea are major contributors to western liberal democracy and to the security of Australia and New Zealand and to Asia Pacific. Taiwan is one of the chain of island bridges to India a country with a long history of democracy and a rapidly growing economy.
The back drop to all this is, of course, that the US cannot go it alone. It needs allies including Taiwan.