Ad‑hoc BW visits fail verification

When a treaty lacks formal inspection rules, reciprocal or goodwill visits can be staged or managed to hide prohibited activity, as hosts can disinfect, limit access, and present dual‑use facilities as benign. Historical memoirs (e.g., Ken Alibek on 1990 trilateral tours) show how such ad‑hoc arrangements produced ambiguous evidence rather than reliable verification. — Highlights that treaty architecture (inspection clauses, verification protocols) is not a technicality but a central determinant of whether arms‑control agreements actually prevent or expose biological weapons programs.