Wikipedia: "Money laundering is the process of concealing the source of money obtained by illicit means."
What is defined as illicit? FED printing money out of thin air, is it illicit? In certain point of view it is, and the amount is enormous. They call it QE, but that is exactly "a process of concealing the source of money obtained by illicit means". It is like saying: Only banks have the right to laundry money freely
In my opinion, money can be robbed, stealed and lost, as long as it's money, there is no question of its legality, because if you trace the origin of today's money, they are all generated by illicit means (printing, or adding 0s to account, not working)
If money laundering is out of question, then BTC will gain some other ground and support
"Illicit" means one thing, and one thing only: when the peasant does an activity that the master wants to do exclusively, then the peasant is acting illicitly.
For example: when you take money obtained by force or fraud and spend it on other stuff to make the original money disappear, it's called "money laundering"; when people doing business as "government" do the exact same thing, it's called "fiscal expense".