Echelon was only finally and definitively unmasked with the publication of the European Parliament report in 2001. https://www.europarl.europa.eu/sides/getDoc.do?pubRef=-//EP/... (Prior to that, the general public would certainly consider you a nutjob for discussing it.)
The EU's historians have recently (2014) published an historical perspective on the writing and impact of that report, which is worth a read: https://www.europarl.europa.eu/EPRS/EPRS_STUDY_538877_Affair...
This is effectively real world history, not the crap you garner from mass media or would-have-you-believe books. Another great classic: the conspicuously missing history of SWIFT, with its own EU parliament discussions.
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