A tax credit is not money you invest. A tax credit is money that you agree not to collect in order to incentivize someone else to invest. The $3 billion would have been a reduction of the $30 billion in tax revenue the deal was projected to generate, thus netting the state $27 billion. The state could afford the $3 billion
because it was getting $30 billion.
As de Blasio pointed out:
Money that does not exist and will not exist, does not exist. I feel like this is a fairly elementary concept. It's not a partisan position, it's more matter of reality. The mayor, a Democrat, apparently not a moron, understands this, even without an economics degree from Boston University.
I used to think disputes like this reflected a difference in priorities, but now I see, in this case anyway, that the problem is something different.