Actually the US is going to build the 8 D/E subs. Personally I would save years and just give Taiwan some Los Angeles class submarines and the training to use them. As for China choosing a time when the US is "preoccupied" well the Navy has nothing to do and it would primarily be a Navy and Air fight. Just a few months back all SEVEN of the US carrier groups were parked near Taiwan to show the ChiComs that the US was not as preoccupied as they thought. And I really wish the US would give them the d**m Aegis warships. Japan has them, South Korea has them. With 96 SM2s each, just 4 of them and the patriots would render the PRC ballistic missile arsenals obsolete. Back when a Taiwanese delegation visited Pearl Harbor in last April, the US hinted at selling them. Infact the Taiwanese delegation toured more of the Arliegh Burke class than anything else before going to Texas to look at the P3 Orions.
Yep,the US AGREED to BUILD 8 D/Es the moments Bush came in-the issue here is not on building them,but the US & Taiwan need to find a design to build subs with.We all know the US doesn't build or design D/Es & has no real plans either,so it would make it dependent on European nations to supply the design for a submarine,which would then carry American sensors & weapons & be built in the US.Sweden,France,Germany,the Netherlands & Russia are the main designers & builders of export D/Es & all these nations have made it adequately clear they won't "help Taiwan" in it's sub requirements(note the wording,they are only saying help,not build).The sub builders like South Korea,India,Turkey,Australia all build license produced D/Es from one of these countries & if they were to try to help Taiwan out,it would affect their own programmes.The only other Sub designing nation is Japan,who don't export anything & will esp be wary of p***ing of China.
PS-in 2002,there were reports that Northrop Grumman had unveiled a variant of the Type-209 D/E sub(A famous German design) to be produced for Taiwan.After that tensions between Germany & China & the US-Germany spat over Iraq sank the deal.Same goes for a plan to build a variant of the Spanish S-80 class sub(which anyways was essentially a French system).