It's very unlikely that US domestic investment will catch up to, or even keep pace with, global growth in demand for semiconductors. The entire world will continue to have a major stake in Taiwan's stability for the foreseeable future.

(The specific Western national-security interest in Taiwanese independence and liberal democracy may be weakened, which could be a long-term problem. But there won't be any impact on the West's willingness to defend Taiwan from a military invasion, armed coup, or other destabilizing attack.)