New Yorkers are a savvy species. We know whom to blame when something goes wrong. Pothole needs filling? It’s the mayor’s job. Film crew blocking your street? Mayor, again. There’s even a popular hashtag for complaints: #deblasiosnewyork.

But what most New Yorkers don’t know is that when we step down into the subway, we cross an invisible border. We’re no longer in Mayor Bill de Blasio’s New York: Everything on the far side of the subway turnstile belongs to the governor.

The MTA is a state agency, with its head appointed by Gov. Andrew Cuomo. The governor controls most of the seats on the MTA’s governing board. And it’s state decision-making that impacts everything from subway repair schedules to public funding levels to how much debt the MTA is allowed to take on.

Last month, an NY1 poll found that fewer than 40 percent of New Yorkers know that Cuomo controls the subways. Most people think it’s de Blasio. That would be an amusing tidbit if the misperception didn’t have serious consequences: Cuomo knows that he won’t be held responsible for the problems we experience every day, so he has little political incentive to fix our subways.

The subways are more popular than ever: Close to 6 million rides every day. Crowding is worse; delays are up. We need a serious infusion of funds to modernize public transit so it can serve the needs of a growing city and stay affordable for people who need it.

Instead, Cuomo is giving transit riders nothing more than an IOU. After promising $7.3 billion in new state funds for transit, the governor’s proposed budget has literally $0 for the MTA’s overdue construction plan.

The legislature is supposed to vote on the state budget this month. If our representatives go along with Cuomo’s plan, it could lead to more crowding, worse service and higher fares for riders.

We live in a democracy, and the answer is clear: Transit riders need to hold our elected leaders responsible for the state of the subways. The first step toward that is to go after the right people.

It’s time for New Yorkers to realize that once we set foot underground, we’re all in #cuomosnewyork.

John Raskin is executive director of the Riders Alliance, a grass-roots organization of subway and bus riders.