Today, what to many on the Left felt like a pipe dream less than a year ago is becoming a reality: democratic socialist Zohran Mamdani is being sworn in as mayor of New York City.

It will not be an easy job. The political and fiscal challenges the mayor will confront in enacting his affordability agenda are numerous. To raise taxes to fund promised programs like universal childcare and free buses, Zohran will need the support of the state legislature in Albany as well as Governor Kathy Hochul, who has said she is opposed to tax increases (though she has softened on this question recently). He will have to deal with budgetary constraints created by outgoing mayor Eric Adams. He will have to deal with fierce opposition from the political establishment as well as New York’s economic elite. And despite his apparent success in charming Donald Trump, it is possible and even likely that the president will revert to his prior stance of hostility and attempt to undermine Mamdani through federal funding cuts or repressive police action.

Overcoming these obstacles to govern effectively and pass his agenda, or even just substantial chunks of it, will be a tall order in its own right. And Zohran making good on his campaign promises is extremely important for building popular support for progressive economic policy and the socialist movement. Working to enact that agenda therefore ought to be a priority of the Mamdani administration as well as of the broader left.