I disagree. I'd argue that much of America actually does have a fetish/obsession when it comes to punishment and an unwillingness to forgive is just one aspect of that same sick impulse. It's partly to blame for the fact that the US locks up more of its own citizens than any other nation on Earth and why prisoners are routinely subjected to inhumane conditions and torture.

You can point out to an American how prisoners are denied healthcare, denied basic personal hygiene products, kept in solitary confinement, beaten, raped, and forced to eat maggot infested food, and there's a good chance you'll be told that's a good thing and that if anything prisoners have it "too good". People who serve their time and who have paid their debt to society are still widely discriminated against and have problems finding work and housing. Even things like the sex offender registry are inappropriate tools intended to allow people to continue to be punished. If someone is a genuine danger to others they should be behind bars, but otherwise they should be allowed to rebuild their life in peace. There is wide support for tough on crime polices even though research shows them to be ineffective at best and counterproductive at worst.

You can see the American obsession with punishment in how police abuses are permitted and how even extrajudicial executions are often considered justified by the public for even the most minor failure to obey an officer's every instruction. In schools zero-tolerance policies carry extremely harsh punishments and literal children (including first graders https://www.youtube.com/watch?v=o8DWqMWJdy8) are handcuffed and arrested for nothing more than acting like children and the school-to-prison pipeline is a uniquely American problem. The US is one of only 5 developed countries that still allow for state-sanctioned killing as a punishment.

It isn't just in the justice system either. A person can spend decades paying taxes that are supposed to entitle them to a safety net in case they fall on rough times, but plenty of people will say that anyone getting food stamps should be punished by not being allowed to spend what little assistance they get on "luxuries" like soda or birthday cakes for their children. I've even seen people argue against birth control because women, especially young women, should be punished with pregnancy or STDs just for having sex.

There's a certain segment of the population which seems as obsessed with others getting the punishment they supposedly "deserve" as they are fearful about others getting good things when they supposedly don't "deserve" them.