TSMC's first fab in Arizona (with an N4 process) was previously scheduled to open in 2024 (https://pr.tsmc.com/english/news/2977) but then was delayed to 2025 (https://www.bloomberg.com/news/articles/2023-07-20/tsmc-to-delay-us-fab-production-until-2025-over-worker-shortages). I expect there will be an opening ceremony, like there was for the recently opened new fab in Japan (https://pr.tsmc.com/english/news/3113) and I will resolve this question at that date. Otherwise, I will resolve the question when there are news reports of production beginning at the fab.
1,000Axios says they started production in 2024, so I think this has already resolved.
FWIW, I'd be interested in follow-up questions about yields and whether they'll hit their target to produce "30% of its most advanced AI chips" in the US.
"TSMC Arizona's first fab is on track to begin production leveraging 4 nm technology in first half of 2025" (2024-04-08).
https://pr.tsmc.com/english/news/3122