Photo is a screen capture from the 9/11 Commission staff report on terrorist travel showing Ziad Jarrah's U.S. tourist visa.

You could still see his mouth and his chin, but only the right side of his face from the nose up.

The rest of the photo and the document on which it was printed — except for the man's first and last name and a broken series of numbers — was charred or burnt away.

Investigators searching the area in Pennsylvania where United Airlines Flight 93 crashed on Sept. 11, 2001, found this telltale piece of evidence.

It was the tourist visa that let Ziad Jarrah enter the United States from Germany.

On the face of it, Jarrah was a clean-cut young man from a wealthy Muslim family in Lebanon, who had moved to Germany to be a student — and only wanted to visit this free and beautiful country as a tourist.

In reality, he was an al-Qaida operative dispatched by Osama bin Laden to carry out the worst terrorist attack in the history of our nation.

In the 15 months before 9/11, Jarrah came and went from the United States at will — entering this country on deceitful terms no less than seven times.

After his first entry, according to a staff report of the 9/11 Commission, he instantly violated the terms of his visa. Yet, again and again, he was welcomed at U.S. airports and granted entry to the United States.

Jarrah did not appear to be a radical Islamic terrorist. He did not seem to have the sort of background that would lead him to hijack a commercial jet and fly it into the ground in Shanksville, Pa., murdering 40 Americans.

"Given his background and personality, Jarrah seemed a relatively unlikely candidate to become an al Qaeda operative," said a statement issued by the 9/11 Commission staff.

"From an affluent family, he studied at private, Christian schools in Lebanon before deciding to go abroad in Germany," said the statement. "He knew the best nightclubs and discos in Beirut, and partied with fellow students in Germany, even drinking beer — a clear taboo for any religious Muslim."

When Jarrah first applied for a tourist visa at the U.S. Embassy in Berlin, the commission staff concluded, he must have seemed like a "strong visa candidate."

"(O)ur review of Berlin visa policy for third-country nationals suggests that Jarrah was a strong visa candidate, given his long residence in Germany (approximately four years), academic involvement in Germany (at two universities) and Lebanese nationality" said the commission staff.

But once inside the United States, Jarrah wasted no time in beginning to execute his terror mission — and violate U.S. immigration law.

"He immediately violated his immigration status by going from the airport straight to full-time flight school," said the staff report.

"Jarrah never filed an application to change his status from tourist to student," says the report. "This failure to maintain legal immigration status provided a solid legal basis to deny him entry on each of the six subsequent occasions in which he reentered the United States."

But he was not denied reentry.

He did secure two drivers licenses in Florida in May 2001 and a third in Virginia on Aug. 29, 2001.

"Jarrah's objective was to crash his airliner into symbols of the American Republic, the Capitol or the White House," said the 9/11 Commission report.

And he did not fail because our federal government had done its job in securing our borders.

"He was defeated," said the commission, "by the alerted, unarmed passengers of United 93."

"It is perhaps obvious to state that terrorists cannot plan and carry out attacks in the United States if they are unable to enter the country," concluded the 9/11 Commission staff report on terrorist travel, published three years after the attacks.

But, even then, the problem had not been fixed.

"Indeed," said the commission staff in 2004, "even after 19 hijackers demonstrated the relative ease of obtaining a U.S. visa and gaining admission into the United States, border security still is not considered a cornerstone of national security policy."

Now, 16 years after 9/11, President Donald Trump appears committed to fixing this problem and securing our border — including where it runs through our international airports.

Terence P. Jeffrey is the editor-in-chief of CNSnews.com.