Sorry to hear about your Iranian Grad Student, but there is good reason for concern. Obama thought so, yet his decission didn't grab as much attention when he did the same. Anyway, since we're discussing the issue, maybe we should look at the order itself...
EXECUTIVE ORDER: PROTECTING THE NATION FROM FOREIGN TERRORIST ENTRY INTO THE UNITED STATES
EXECUTIVE ORDER
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Protecting the Nation from Foreign Terrorist Entry into the United States
By the authority vested in me as President by the Constitution and laws of the United States of America, including the Immigration and Nationality Act (INA), 8 U.S.C. 1101
et seq., and section 301 of title 3, United States Code, and to protect the American people from terrorist attacks by foreign nationals admitted to the United States, it is hereby ordered as follows:
Section 1. Purpose
. The visa-issuance process plays a crucial role in detecting individuals with terrorist ties and stopping them from entering the United States. Perhaps in no instance was that more apparent than the terrorist attacks of September 11, 2001, when State Department policy prevented consular officers from properly scrutinizing the visa applications of several of the 19 foreign nationals who went on to murder nearly 3,000 Americans. And while the visa-issuance process was reviewed and amended after the September 11 attacks to better detect would-be terrorists from receiving visas, these measures did not stop attacks by foreign nationals who were admitted to the United States.
Numerous foreign-born individuals have been convicted or implicated in terrorism-related crimes since September 11, 2001, including foreign nationals who entered the United States after receiving visitor, student, or employment visas, or who entered through the United States refugee resettlement program. Deteriorating conditions in certain countries due to war, strife, disaster, and civil unrest increase the likelihood that terrorists will use any means possible to enter the United States. The United States must be vigilant during the visa-issuance process to ensure that those approved for admission do not intend to harm Americans and that they have no ties to terrorism.
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https://www.whitehouse.gov/the-pres...-nation-foreign-terrorist-entry-united-states