"What makes Tor different from the usual thesaurus-full of government projects is that Tor is essentially a very elaborate math trick, using layers of math puzzles to create a network-within-the-network. That math is being implemented in front of a global audience of millions of sophisticated watchers. It is likely the most examined codebase in the world. It has been subjected to multiple public audits. The math, well known and widely standardized, will work for everyone, or it will not, whoever pays the bills."
"Trusting mathematics" would be a much more accurate claim if we were talking about mix networks, such as Loopix (https://arxiv.org/abs/1703.00536). But Tor is vulnerable to confirmation attacks to varying degrees, (depending on whether you are accessing clearnet or not, of course) which is very much worth noting in the context of a global passive adversary.
from https://pando.com/2014/12/09/clearing-the-air-around-tor/