Sometime last January, several agents belonging to Israel's intelligence service, Mossad, approached a nondescript warehouse in Tehran.  After disabling a few alarms and bypassing other security measures, the agents entered the building. 

The agents had hit the jackpot.  Over six and a half hours, the agents removed tens of thousands of documents relating to Iran's nuclear program.  The documents included warhead designs and information on how other countries had assisted Iran in its nuclear program.

The upshot is that the documents – as Israeli prime minister Benjamin Netanyahu said in a speech last April when he made the raid public – prove that Iran has been lying about its nuclear program.

Washington Post:

A large team of Israeli experts has continued to mine the document trove for new revelations while simultaneously sharing the material with U.S. and European intelligence agencies as well as with the International Atomic Energy Agency, or IAEA, the U.N. watchdog in charge of monitoring Iran's nuclear activity.  Officials shared recent discoveries with a small group of Western news outlets last week, arguing that the newly uncovered evidence of Tehran's advanced nuclear weapons research – along with its elaborate efforts to conceal the activity while preserving the technical know-how for possible future use – shows that Iran cannot be trusted.  Iran has disputed the authenticity of the documents obtained by Israel, calling them forgeries.  Officials at Iran's U.N. mission in New York did not reply to a request for comment.

"This archive explains why we have doubts," a senior Israeli official told U.S. journalists at the briefing in Tel Aviv.  The official, like others involved, insisted on anonymity in discussing highly sensitive documents and intelligence operations.

"It explains why the [nuclear deal] to us is worse than nothing, because it leaves key parts of the nuclear program unaddressed," the official said.  "It doesn't block Iran's path to the bomb.  It paves Iran's path to the bomb."

When the Post and other pro-Iran nuclear deal commentators try to point out that there's "nothing new" in the documents, they are only half right.  In fact, the information confirms vital intelligence that, at one time, was merely speculation or educated guess work.

Some of that intelligence that could only be speculative involved the military base at Parchin.

Wall Street Journal:

Iranian nuclear scientists, two of whom later were assassinated under mysterious circumstances, are quoted in one document discussing the need to distinguish between "overt" nuclear research activities, which could continue because they could be shown to have peaceful purposes, and "covert" activities that had to be hidden because they could only be attributed to a nuclear-weapons program.

A series of other documents and photos purportedly involve one particularly sensitive Iranian facility, within a military complex known as Parchin, which the IAEA long suspected housed a firing chamber used to test explosives that could be used to ignite a nuclear explosion.

When the IAEA finally gained access to the facility in 2015, it found no such chamber, but said extensive demolition and refurbishing of the site had seriously undermined the agency's ability to determine whether such a chamber had been there.

The new materials include more than a dozen photographs of what Israeli intelligence officials said was the explosives chamber at Parchin, as well as reports on experiments conducted there.

IAEA "access" to Parchin sums up the idiocy of the nuclear deal.  Inspectors were allowed inside the base, but most of the "inspection" involved Iranian officials:

Act II begins with the negotiations on the peculiar method by which the IAEA would conduct its inspection of the building, the major part of which would be carried out by the Iranians themselves, thus assuring that the results would not contradict their declarations that no improper activities took place in that building.

In spite of the probable futility of the inspections, they were carried out in September 2015 and were described thus by the director general: "The Iranian side played a part in the sample-taking process by swiping samples. The Agency can confirm the integrity of the sampling process and the authenticity of the samples[.]"

Iran insisted that there was no nuclear research being done at Parchin.  The documents show that to be a lie.

Anyone who reads about these documents and isn't totally in the tank for Iran almost certainly realizes that Trump's ditching the nuclear deal was the right choice.