Iran is doubling down on the missile strategy that took out 5% of the world's oil supply

• Iran is doubling down on the success of last summer's cruise missile attack on two Saudi oil facilities by positioning advanced weapons around the Middle East from Yemen to Lebanon, a NATO source told Business Insider.
• "The Iranians learned that they have a longer leash for conducting operations against the Saudis and UAE than they realized under the Trump administration," the official said.
• Iran has been widely blamed in the west for cruise missile and drone attacks on two Saudi Arabian oil facilities in September. The attacks temporarily knocked 5% of the world's oil supply offline.
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Iran is doubling down on the success of last summer's cruise missile attack on two Saudi oil facilities by positioning advanced weapons around the Middle East from Yemen to Lebanon, a NATO intelligence official based in the region told Business Insider.

"The Iranians learned that they have a longer leash for conducting operations against the Saudis and UAE than they realized under the Trump administration," said the intelligence official from a NATO state. The official cannot be named because they are on active duty and lack permission to speak on the matter from their government.

The source claims that Iran is launching an aggressive expansion by pushing out advanced missiles and components to Iran's allies and proxies in Yemen, Iraq, Syria and Lebanon. That claim has been verified by a slew of recent public statements by US military and intelligence officials.

"The Iranians did not expect a complete lack of response to the attacks on Abqaiq-Khurais oil fields from the United States," the official said of the attacks, which knocked around 5% of the world's oil supply offline.

"It appears to have been as much a test of American and NATO reactions as it was a warning to everyone that Iran can do far more damage to Western interests in the Gulf than the US is willing to do to Iran in return."

Iran has pushed out increasingly sophisticated guided missile and cruise missile systems to their allies in recent years.

On Wednesday, the US Navy announced that an unflagged ship filled with missile components bound for Iran's Yemeni allies, the Houthis, had been seized last month.

In a statement to NBC News, a Pentagon official said that the seizure of the ship was the seventh such seizure in five years, and contained by far the most advanced missile guidance components. The ship itself was described as a light craft that was not flying a flag, but was crewed by Yemenis.

Iran claimed the Saudi oil attack was a Houthi operation, but US officials have repeatedly claimed that it came from southwestern Iran, and the cruise missiles used flew first over Iraq before turning southeast into Saudi Arabia.

On Wednesday, US military and intelligence officials confirmed to the New York Times that Iran was using the continuing political crisis in Iraq to send advanced missile systems to their Shiite militia proxies, who have often been targeted by demonstrators. Iraq is in the midst of deadly demonstrations that have roiled the country's political landscape.

The US announcement comes at little shock to countries region, as Israel has targeted such transfers of missiles and advanced gear in Iraq, Syria and Lebanon with scores of airstrikes over the past few years.

Israel has consistently claimed that such transfers represent a red line that cannot be crossed without a strong Israeli military response.

But despite these efforts, one Hezbollah commander in Beirut reached by encrypted messenger claimed that the Israeli strikes have offered little more than an inconvenience to a powerful network of like-minded Iranian allies.

"The resistance has better missiles and equipment than it did last year, or the year before that," said the commander, who commands dozens of fighters in Beirut's southern suburbs and works in counterintelligence operations.

"The Americans and Zionists [Israeli nationalists] have stopped some transfers but they can't stop all of them. If they hit something there was probably five transfers that were not hit.

"We control the land in these places and the Israelis have never learned that controlling the air isn't enough when your enemy controls the land."