“ In the South China Sea, Washington contests Beijing’s territorial claims by sending warships into Chinese waters and claiming the deployment is a “freedom of navigation operation.”
Chinese waters are the 12 NM standard, not the entire South China Sea. That statement from the article clearly shows the pro CCP bent of the author. And yes, without those freedom of navigation patrols, China would close the Taiwan Strait.
12nm is territorial water but there is also the concept of Exclusive Economic Zone per the UN. EEZ stretches 200 miles out to sea but it’s not territorial water. It’s only for economic development. It certainly does not allow for building artificial islands for military purposes or restricting navigation for other countries.