The 2 F-15s that crashed into Ben Macdui in 2001 did so, at least partially, because their American pilots did not understand the nuances of terrain avoidance responsibility under UK ATSOCAS at the time. You can argue that they should have understood but neverthless regulatory alignment is a desirable objective in an environment which has no physical boundaries.
The military are not operating under ICAO or ANO regulation so this is not a good argument.