Daniel Penny has been smeared as a vigilante and a racist, but the truth is slowly being revealed at his trial: The Marine vet tried to do the right thing and protect others in an impossible situation — and got arrested and charged with manslaughter for it.

On May 1, 2023, mentally ill homeless man Jordan Neely charged onto an F Train and began ranting at his captive fellow passengers.

Witnesses have said that Neely claimed he “didn’t care about going back to jail” and ominously warned that “someone is going to die today” before Penny put him into a hold to subdue him, which led to Neely’s death after police arrived.

The prosecution wants jurors to believe that Penny was overzealous, that he overreacted to Neely’s threats.

Most of all, the DA’s office wants to remind jurors that Penny is white and Neely was black, as Assistant DA Jillian Shartrand did when she repeatedly referred to Penny as “the white man” in court.

The intent of that is obvious: Make this case about race, not safety.

But the prosecution’s own first witness threw cold water on that cynical tactic.

On Monday, high-school student Ivette Rosario, who caught a shaky video of the encounter as she trembled with fear, testified that Neely’s menacing made her so nervous she thought she was “going to pass out,” and noted: “I’ve been in situations on the train where stuff was said, but not like this.”

Rosario thought she was in real danger, as many others on that train likely did.

That was what made Penny leap into action, not his skin color or Neely’s.

Neely’s story is a tragic one: He had a history of mental illness and was even hospitalized under a plea deal in an assault case, yet was allowed to sign himself out of inpatient treatment.

If there’s a villain in this case, it’s the inept and hands-off mental-health system that let Neely be on the streets that day, instead of in a psychiatric bed.

It’s a justice system that cares more about race than keeping New Yorkers (of all races) safe.

Rosario made another important point for the defense: Even though in her video, other passengers can be heard telling Penny to let go of Neely, she said she didn’t hear the protests “in the moment” on the train.

Likely because it was a chaotic, harrowing situation that no one on that train car should have been in.

We’ll never know if Neely would have followed through on the threats he made on the train that day, but one thing’s for sure: The city’s refusal to do its job led to Neely’s death.

Gotham’s broken mental-health system and loony leftism should be on trial, not Daniel Penny.