At least in the UK...
At least in the UK, you can challenge mass surveillance. Here in the United States of America, fat chance. People have tried and have had their cases dismissed because of 'State Secrets Privilege' which caused necessary evidence to be withheld in court. There have been criminal convictions where the evidence used in the prosecution was withheld from the defense because it was 'classified,' which is a blatant violation of The Constitution. But of course, any dissident voices are routinely silenced so the public at large doesn't know what is going on.
https://en.wikipedia.org/wiki/State_secrets_privilege