Due process may still hold true (idk, inal, sounds about right) but there are a number of long-standing regulations governing re-entry. Let's not overlook the fact that there are regulations in the US regarding re-entry for green card holders which sound very reasonable to me - especially when compared to immigration law in other countries.

* have abandoned or relinquished your status as a lawful permanent resident

* have been absent from the U.S. for a continuous period of over 180 days

* engaged in illegal activity after leaving the U.S.

* left the U.S. while in removal or extradition proceedings

* committed one of the crimes named in § 212(a)(2) of the I.N.A. (such as one crime of moral turpitude (CMT), a drug or trafficking crime, multiple crimes, prostitution, money laundering, security violations, and so on), unless later granted relief under Section 212(h) or 240A(a)...

* are attempting to enter at a time or place other than as designated by immigration officers.

* if you have any criminal violation on your record, you should not leave the U.S. without consulting with an experienced immigration attorney first.

* it's a crime for immigrants not to submit immediate notifications to U.S. Citizenship and Immigration Services (USCIS) of their changes of address.

The one that confuses me a bit is "are attempting to enter at a time or place other than as designated by immigration officers".

Now, the issue of allowing re-entry from a very limited list of countries that are hotbeds of religious terrorism when the vetting process is suspect. That's the focus here.