The clearest evidence of the Iran link came in January 1990, when Pakistan's army chief of staff conveyed his threat to arm Iran to a top Pentagon official. Henry S. Rowen, at the time an assistant defense secretary, said Pakistani Gen. Mirza Aslam Beg issued the warning in a face-to-face meeting in Pakistan. "Beg said something like, 'If we don't get adequate support from the U.S., then we may be forced to share nuclear technology with Iran,'" said Rowen, now a professor at Stanford University. Rowen said former President Bush's administration did little to follow up on Beg's warning. "In hindsight, maybe before or after that they did make some transfers," Rowen said. Rowen said he told Beg that Pakistan would be "in deep trouble" if it gave nuclear weapons to Iran. Rowen said he was surprised by the threat because at the time Americans thought Pakistan's secular government dominated by Sunni Muslims wouldn't aid Iran's Shiite Muslim theocracy. "There was no particular reason to think it was a bluff, but on the other hand, we didn't know," Rowen said.