David Frum on the Obama immigration order:

The decision to grant residency and work rights to young illegal aliens who meet certain conditions is an amnesty in all but name. A conditional amnesty, yes, but amnesty. The trouble with amnesty has always been the incentive effects. It's possible that amnesty may be a necessary final stage in immigration reform, but to put amnesty in place before effective enforcement measures are in place—and before authorities are certain that as many illegals as possible have voluntarily repatriated—is to invite another wave of illegal migration just as soon as business conditions improve.

Frum also argues that the middle class could suffer the most from this:

In a time of very high unemployment, it seems simply reckless to invite future waves of migration—and especially of the low-skill, low-wage migration that America has mostly attracted over the past four decades.
Every serious economic study of immigration has found that the net benefits of present policy are exceedingly small. But that small net is an aggregate of very large effects that cancel each other out. The immigrants get higher wages than they would have earned in their former country. The affluent gain lower prices for in-person services. Lower-skilled native-born Americans face downward wage pressure. In any other policy area, people who consider themselves progressive might be expected to revile a policy whose benefits went to foreigners and the rich, and whose costs were born by the American poor. Immigration policy baffles that expectation.