The Pentagon and National Security Council significantly underestimated Iran’s willingness to close the Strait of Hormuz in response to US military strikes while planning the ongoing operation, according to multiple sources familiar with the matter. President Donald Trump’s national security team failed to fully account for the potential consequences of what some officials have described as a worst-case scenario now facing the administration, the sources said. And now it may be weeks before the administration’s efforts to alleviate the intensifying economic fallout take hold, officials said Thursday, including high-risk naval escorts of oil tankers through the strait that the Pentagon...