Secret Memo Details U.S.’s Broader Strategy to Crack Phones

Silicon Valley celebrated last fall when the White House revealed it would not seek legislation forcing technology makers to install “backdoors” in their software -- secret listening posts where investigators could pierce the veil of secrecy on users’ encrypted data, from text messages to video chats. But while the companies may have thought that was the final word, in fact the government was working on a Plan B.

In a secret meeting convened by the White House around Thanksgiving, senior national security officials ordered agencies across the U.S. government to find ways to counter encryption software and gain access to the most heavily protected user data on the most secure consumer devices, including Apple Inc.’s iPhone, the marquee product of one of America’s most valuable companies, according to two people familiar with the decision.