Inside the risky bat-virus engineering that links America to Wuhan technologyreview.com/2021/06/29/102…
This is a very good article - one of the most incisive I have read so far - which describes the absurdity of doing spike-inserts under BSL-2, a totally inadequate level.
For another proof that the WIV was often working at BSL-2 on bat coronaviruses, check their (deleted) page:
Note that we got many reassurances from China that the WIV P4 was extremely safe - a total diversion given that bat coronaviruses were not studied at P4.
For some reason the WIV never mentioned its P2s and P3s - and that page its long gone (archive: bit.ly/2SzRRrw).
The key issues is that P4 is slow and costly. One is never going to do many experiments or write many papers at P4.
P3 is still quite slow too and you cannot get that many people working there, with all the necessary training and equipment.
In the end the WIV (Zhengdian site) has 20 P2s, 2 P3s and 6 P4s labs (3 standard, 2 animal suites + 1 dissection).
It's actually not many P3s at all, only *2* - which is rather odd.
But plenty of P2s.