Having had the time to actually look at the E Mails in Question.
This stuff is collected Electronically and then filtered by whatever system is being used by the Agency who is intercepting the Transfers.
Even if it's Encrypted which does raise Red Flags to these Agencies and the Filtering Software that Encryption is broken generally by the Encryption Back Doors supplied by the Encryption Makers and supplied to the Authorities for instance the Software Package known as Microsoft Coffee which is not for general consumption.
What the events of 9-11 actually showed is that the data had been collected but not actually seen for another 3 or 4 months after it was transmitted well after the event it was supposed to prevent anyway. The Agency tasked with this Interception is completely swamped with the daily traffic it monitors and the way that the Government Under-Resourced it.
So the end result is you will get away with what you are intending but a few months after the event if you have not already killed yourself you are going to get caught and you will serve the time for your crimes.
Like all Law Enforcement it is playing Catchup and not actually preventing much at all.
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