WASHINGTON — The intelligence that caused the White House to escalate its warnings about a threat from Iran came from photographs of missiles on small boats in the Persian Gulf that were put on board by Iranian paramilitary forces, three American officials said.
Overhead imagery showed fully assembled missiles, stoking fears that the Islamic Revolutionary Guards Corps would fire them at United States naval ships. Additional pieces of intelligence picked up threats against commercial shipping and potential attacks by Arab militias with Iran ties on American troops in Iraq.
But just how alarmed the Trump administration should be over the new intelligence is a subject of fierce debate among the White House, the Pentagon, the C.I.A. and America’s allies.
The photographs presented a different kind of threat than previously seen from Iran, said the three officials, who spoke on the condition of anonymity because they were not authorized to talk about it publicly. Taken with the other intelligence, the photographs could indicate that Iran is preparing to attack United States forces. That is the view of John R. Bolton, President Trump’s hard-line national security adviser, and Secretary of State Mike Pompeo.
But other officials — including Europeans, Iraqis, members of both parties in Congress and some senior officials within the Trump administration — said Iran’s moves might mostly be defensive against what Tehran believes are provocative acts by Washington.
Either way, the questions about the underlying intelligence, and complaints by lawmakers that they had not been briefed on it, reflect a deep mistrust of Mr. Trump’s national security team.