There was always a two-part calculation to Gov. Andrew M. Cuomo’s plan to restrict the growth of property taxes in New York. The first, and critical, component was to impose a tax cap preventing local governments and school districts from reaching too easily into the pockets of over-taxed New Yorkers. Cuomo accomplished that goal, to the relief of millions of New York taxpayers.

But the second part remains undone. Once the state limited the tax increases that a local government or school district could impose, it also needed to offer those entities some relief from the scores of unfunded state mandates that hang around their necks like an anchor on a drowning man.

Primary among these are the Taylor Law, which regulates how governments and labor unions negotiate contracts, and the associated Triborough Amendment, which keeps the provisions of lapsed contracts in place pending a new agreement.

Both those laws need to be reconsidered – not thrown out, as there are some necessary protections for unions within them – but changed so that labor unions in municipalities and school districts are incentivized to negotiate contracts that reflect current conditions, rather than just sitting tight and letting the taxpayers twist in the economic wind.

But there are other mandates that Albany should remove from the backs of local taxpayers. The list of possible targets is long and includes Medicaid, youth detention, child welfare, probation, indigent defense, preschool, pensions and public assistance.

None of these can be called unworthy of public support, but the cost has become too high, especially in upstate New York, where the steady loss of manufacturing jobs has eroded the tax base and left fewer and fewer taxpayers to shoulder the cost.

It would not be fair to suggest that Cuomo has done nothing to relieve local taxpayers. First and foremost is the tax cap, itself, which generally holds property tax increases to 2 percent. School districts can override the cap with 60 percent support from voters.

But Cuomo has done more, agreeing to gradually take over increases in state Medicaid costs and crafting a new pension tier that will save taxpayers money in years to come.

Indeed, Cuomo has been the best friend taxpayers have had in the governor’s office in memory. But it’s not enough simply to tell mayors and county executives and school district leaders that he has budget troubles of his own and they just need to make hard decisions and tough it out.

Of course they have to do that. But there’s more to it. Cuomo also has to show that he understands the crushing burden of unfunded state mandates, which can account for nearly all of a county’s property tax levy. That’s no more sustainable than the pensions that are strangling the state. Cuomo needs to do something about the problem, or at least lay out plans for it when the economy shows sufficient signs of improvement.