There is a new award documentary called "The Fare" (on Facebook you can view trailer and info about at : The Fare: An AFI Thesis) that I hope all people, including the op/ed writer and those who encourage youth to come here Illegally should watch.  
Topic is about youth who become victims of sex traffickers, "enslaved" by cartels and forced to commit illegal actions or who are "sold or indentured" as laborers, in the fields, factories, and in homes.
Youth who come here alone and their parents who send them, are given the false impression and hope about staying here, are very vulnerable to becoming victims. 
That is one of the reasons why legislation needs to be passed, to stop and discourage any more youth from coming here illegally and to finally give all the Dreamers now registered citizenship. 
Most Americans do NOT want the Dreamers who are here deported !  Congress has not acted on this, despite the first legislation being introduced in 2001. Congress makes laws not the POTUS.