TSMC is not really that important. It’s currently only useful for the cutting edge of CPUs, and especially for mobile phones, that can get the battery boost from using a more efficient processor.
Military hardware uses CPU technology that’s 10+ years old, of which the Chinese are capable of fabricating themselves on the mainland. The stuff needs to be rugged, and likely, radiation-proofed.
And besides, isn’t it easier for Switzerland to just launch missiles at the bridges, instead of actively maintaining explosive devices on each bridge?