Pressure against individuals:
To put pressure on people to get them to do your bidding. To compel people to turn up evidence on bigger fish or your family members. To compel someone to be a patsy for a different crime. To compel celebrities to come out in support of the security state.
Nationally (or bragging rights):
To look good to other countries when we ask for loans ("we're a secure nation- we could arrest all of these people if we wanted to."). To negotiate with prison-building companies (untapped arrests are potential prisons). To compel additional budgeting for high-tech crime-fighting research and equipment. To inflate one party's credibility pre-election ("we turned up all these bad guys."). As bargaining tokens in international deals ("we'll turn in this bad guy of yours if you buy our $million radar"). To bolster Big Pharma's stance that mass-narcotics are necessary ("look how many people self-medicate with dangerous cannabis, they should be taking prozac instead.").
Yikes. I prefer to think that the government would not be that evil, but then again, that's just me choosing ignorance/optimism over thinking about how bad things could actually be.
Nationally (or bragging rights): To look good to other countries when we ask for loans ("we're a secure nation- we could arrest all of these people if we wanted to."). To negotiate with prison-building companies (untapped arrests are potential prisons). To compel additional budgeting for high-tech crime-fighting research and equipment. To inflate one party's credibility pre-election ("we turned up all these bad guys."). As bargaining tokens in international deals ("we'll turn in this bad guy of yours if you buy our $million radar"). To bolster Big Pharma's stance that mass-narcotics are necessary ("look how many people self-medicate with dangerous cannabis, they should be taking prozac instead.").