Jessica Vaughan of the Center for Immigration Studies offers "Study Reveals 72 Terrorists Came From Countries Covered by Trump Vetting Order" [1]. Her goal is to show that Donald Trump's travel ban (or Muslim ban) will help keep the U.S. safe.

In fact, the study unwittingly shows a major way Trump's ban won't keep the U.S. safe but is in fact one of the dumbest examples of "security theater" yet.

Vaughan uses a list of convicted terrorists as her source [2] and there might be issues with that list as she admits. However, the bigger issue is that most of those in the list come from countries that aren't covered by Trump's ban. In fact, I only had to count the countries of origin from the first 24 pages of the 65 page list before I'd found around 105 convicted terrorists who'd originated in countries not covered by Trump's ban [3]. Vaughan only found 72 from the Trump ban countries in the whole document.

If your goal is to keep the U.S. safe, a brainless ban on specific countries won't work: terrorists can come from Canada (at least 4), Colombia (at least 9), and the U.K. (at least 3). We aren't going to ban travel from those countries, so smarter thinking is needed.

What's needed is just stricter screening on those entering the U.S. If someone doesn't have a paper trail, they don't get in. Done without mentioning a region or a religion, that would both keep the U.S. safe and - unlike Trump's ban - it could be implemented. That way those who pose no danger from Libya can enter, while those in France, Canada, or Mexico who do pose a danger wouldn't be allowed in.

Are Vaughan and CIS pushing something that would both keep the U.S. safe and could be implemented? No, they're acting as apologists for Trump's brainless ban and claiming it can be implemented even as it's tied up in the courts:

President Trump's vetting order is clearly legal under the provisions of section 212(f) of the Immigration and Nationality Act, which says that the president can suspend the entry of any alien or group of aliens if he finds it to be detrimental to the national interest. He should not have to provide any more justification than was already presented in the order, but if judges demand more reasons, here are 72.

There are at least 105 reasons in Vaughan's own document showing how Trump's brainless ban won't keep the U.S. safe.

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[1] cis dot org/vaughan/ study-reveals-72-terrorists-came-countries-covered-trump-vetting-order
[2] cis dot org/sites/cis.org/ files/Terror%20Arrests.senate%20judiciary.pdf (cached)
[3] The list spans 65 pages. Here's a count of the listed countries of origin from the first 24 pages. The number after the country indicates how many if there were more than one. This list doesn't include those countries listed in the document on Trump's ban:

Afghanistan 5
Australia
Bangladesh 2
Bosnia 2
Canada 4
Colombia 9
Dominican Republic
Egypt 4
Eritrea
Ethiopia 2
Greece
Guatemala
Guyana 3
Haiti 2
India 4
Kazakhstan 2
Kosovo
Kuwait
Jordan 2
Lebanon 7
Mali 3
Mexico
Morocco 2
Nicaragua
Nigeria 2
Pakistan 18
Palestine
Paraguay
Peru
Philippines
Qatar
Russia
Saudi Arabia
Senegal
Singapore
Sri Lanka 2
Tanzania
Trinidad & Tobago
Tunisia
Turkey 2
United Kingdom 3
Uzbekistan
Venezuala
Yugoslavia

There was also one person listed as "Canada,Pakistan", included as one person in the 105 figure above.