You can shortchange the system only so much and get away with it. As the Times article showed, Mr. Pataki in 1995 started a trend of steering tax revenue away from mass transit to plug holes in other parts of the state budget. At least $850 million has been redirected in this manner over the past two decades. Mr. Giuliani, faced with a municipal budget shortfall in 1994, slashed the city’s yearly contribution to the M.T.A. by $400 million, equivalent to $675 million today. Subsequent state and city leaders stuck to this rob-Peter-to-pay-Paul pattern.

Labor contracts were signed even though not fully affordable. Instead of relying on steady revenue streams to pay for it all, the state, which controls the M.T.A., chose to borrow — a lot, with future generations left to pick up the tab. Interest payments now come to $2.6 billion a year, or 16 percent of the transit agency’s budget, a share expected to rise to 20 percent in a few years.

However misguided their predecessors may have been, Governor Cuomo and Mayor de Blasio own this crisis. New Yorkers are still waiting for them to set aside mutual antagonism to figure things out, starting with where they will get the money needed to rehabilitate the wounded system. Instead of teamwork, we have dueling plans. The governor offers a congestion-pricing concept that is enticing in theory — if only he’d elaborate on what it would look like in reality. Months have gone by without his offering any details. For his part, the mayor sticks to a “millionaires tax,” with scant reason to believe that State Senate Republicans and their tag-along squad of allied Democrats would accept it.

The need now is for leadership comparable to what New York had for a while in the 1970s when the entire municipal government, not just the subways, stood on the brink of collapse. That was when everyone — bankers, union leaders and state and local politicians — all worked together to restore fiscal health. It required sacrifice by everyone.

That cohesion is absent now. But it’s desperately needed for costs to be kept under control, for the city and the state to each pay its fair share and for priorities to be set so that essential repairs count more than, say, amenities like cellphone charging stations on subway platforms.

Perhaps it’s time to create a ’70s-style coalition. That could be an assignment for Andrew Byford, who led a turnaround of the once-troubled Toronto transit system and on Tuesday was put in charge of New York’s subways and buses. High-tech whizzes or Wall Street hotshots, ad agency employees or hard-hat laborers — they all rely on mass transit and feel the pain of an undependable system.

In truth, as troubled as mass transit is, it isn’t as woebegone as it was in the ’70s. Not yet. But must it take sliding back to that abyss for political, business and labor leaders to get it? They have it in their power to be the parents of a new success, not guardians of a failure that is most assuredly not an orphan.