This probably explains why green card holders were included in Trump's order

ABC News:

Thousands of green cards have been mishandled over the past three years, according to a new Department of Homeland Security inspector general report.

Electronic system errors have caused at least 19,000 cards to be issued as duplicates or with incorrect information — such as name, date of birth, photo and gender — the report says.

But the head of U.S. Customs and Immigration Services (USCIS), which manages immigration benefits, said that several of the report’s conclusions were overstated.

The USCIS director said that the agency did not issue green cards to any individuals who were not eligible to receive them and that the number of cards containing errors were only a “tiny percentage” of the total issued each year.

He added that for the cards to be misused, they would have to fall into the hands of someone with “malicious intent” and a physical resemblance to the card’s intended recipient.

In some cases, green card applicants who should have received a card good for two years were issued one valid for 10 years.

During the past year, USCIS inadvertently sent more than 6,000 duplicate green cards to applicants.

“It appears that thousands of green cards have simply gone missing. In the wrong hands, green cards may enable terrorists, criminals and undocumented aliens to remain in the United States,” said DHS Inspector General John Roth.

The report follows up on the watchdog’s March finding that USCIS possibly sent hundreds of green cards to the wrong addresses.

The problem was “far worse than originally thought,” according to Roth.

In September, Roth found that because of issues with USCIS digital fingerprint records, the U.S. government mistakenly granted citizenship to at least 858 immigrants who had pending deportation orders.
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This story is dated November 21, 2016, shortly before the election.  The media hysterics since the Trump order was issued apparently overlooked this information and the Trump administration apparently failed to highlight it in explaining the green card inclusion.