The drugs in question appeared to be effective  only when administered during or shortly after a traumatic event. How then could we make, and make on the spot, the prospective judgment that a particular event is sufficiently terrible.

【简析】

1. 两个make 的宾语都是the prospective judgment，而that a particular event is sufficiently terrible， 是the prospective judgment 的同位语从句。

2. 两个make 虽然并列，但语义并不重叠。一个是“作出”，一个是“当场作出”。

3. make the prospective judgment：作出前瞻性判断。