Last year, in his first budget, Mayor Bill de Blasio increased funding to NYC's library system, bringing its funding to $323 million -- a $22 million gain. It was the first such increase in six years, dating back to de Blasio's predecessor, Michael Bloomberg. Advocates applauded the gain, hoping it marked a momentum shift that would lead to an effort to fully restore the $65 million per year in funding the city libraries had lost since 2008.

But when de Blasio released his fiscal year 2016 budget this month, operational library funding stood at $313 million, a $10 million cut from last year.

Administration officials pointed to a $300 million boost to the libraries' 10-year capital plan.

Library advocates say they need $1.4 billion for renovation and maintenance. But whatever the number, a new or renovated library building is useless if it has limited staff, hours and resources.

The mayor, who proclaims a fight against income inequality as his cornerstone, must restore the $65 million to bring the libraries to pre-recession levels.

The city's more than 200 branches are used most by low-income families, children and seniors -- those whom de Blasio has promised to help. City kids who don't own computers depend on libraries for Internet access and word-processing homework. Job seekers depend on local branches for workshops and search efforts. Families go to story times and seniors go for classes, meetings and more.

Additional funding could allow the libraries, which have cut 1,000 employees since 2008, to restore weekend and evening hours, add computers or books, or hire a librarian where one is needed. All of this has to come with stronger library leadership and better money management, especially on the heels of last year's lavish spending by the former Queens Public Library president.

Restoring these funds would require less than a tenth of 1 percent of the mayor's total $78.3 billion budget. That seems like a small, painless step toward making de Blasio's self-proclaimed progressive agenda a reality.