but the military had jets in the air, had intelligence showing exactly what each nation in our world was capable of. in specific cases there must be vast doubt over any reasonable explanation of what people really saw.
curious to note that the MOD actually thought that the investigation and the continuing reports from people (including military personnel) would actually harm other projects current or proposed, that would be searching for life. Now the MOD officially are open minded, but between the lines we see that they were still open minded then, just wanted concrete proof. Maybe their own frustrations made them make the comments they did. Or was there pressure from the old school persons in power to clamp down on these things? Until classified documents surface explaining why the actions were taken in this classified document we will never know the truth about what motivated this decision without concrete proof UFO's did not exist!
(and as to the language/spelling, i think Isaac Asimov was actually commenting on problems for american people with the difference between "British" and "English" OMG! It's like he didn't know that the "British Isles" now known as "United Kingdom" contains "England" where we speak "English". Theres no such thing as the "British" language

Scotland, Wales, EIRE and Northern Ireland are also contained within the UK, with Scottish, Welsh and Irish being the other languages spoken)