One of the main points of the U.S. constitution is to provide checks and balances so that one branch of government cannot ac t unilaterally without oversight. For the executive branch to argue that in this case there is no way to challenge it is disingenuous at best and at worst, as this judge pointed out, unconstitutional. It's frustrating to me as a citizen that if a government agency decides it has a problem with…
A lot of legislators do not like the Judicial branch and consider it to be an annoying restraint on their lawmaking power; what looks like tension between the Executive and Judicial branches is often as not a proxy for Legislative claims. Whenever you see a piece of legislation with phraseology like '[officer of some executive branch agency] shall do x, y, z, in the following fashion...' pay attention to the word shall. In law this is understood to make the action mandatory, and where the law is very specific on procedures and actions it's basically an attempt to micromanage the operation of the agency in question.
Consider the following imaginary law:
If any person wears white after Labor Day, the head of the Fashion Police shall cause that person to be arrested and fined $1,000. This procedure shall not be subject to judicial review.
Now if you're the Fashionista-general, you have no choice but to arrest people wearing white after Labor Day [for non-Americans, wearing white after late September is jokingly regarded as an offense against good taste]. Failure to do so clearly violates the oath of office required of office-holders in the Executive branch. And the same law says that you don't get to complain about this in court, so judges are supposed to dismiss your case without even giving it a hearing. That will make people mad with the Fashion Police and frustrated with the Courts, even though the blame for this law lies with the Legislature.
Here's an example of a real law that operates this way, from a current immigration statute: http://www.law.cornell.edu/uscode/text/8/1252
Note section (a)(2)(A)(i): the law applies to people who receive orders of removal, aka deportation orders (a); it's explicitly not subject to judicial review (2)(A); and the procedures for dealing with individual cases are very narrowly specified in the section linked to from clause (i), with a lot of detail specifying how people shall be categorized and treated.