Here is an excellent article at National Review:

On his way out the door, Nanny Bloomberg strikes again: New York City is on the cusp of banning anyone under 21 from buying cigarettes or e-cigarettes.

**SNIP**

There's no doubt smoking is unhealthy (although reflect for a moment on the fact that New York teens too young to smoke can legally obtain an abortion, without parental consent). But it's no sure thing that the new ban will be effective.

The emphasis above is mine

Read more at National Review.