MOUNTAIN VIEW, Calif. (Reuters) - U.S. Defense Secretary Jim Mattis said on Thursday an Obama-era experimental defense outpost in Silicon Valley would grow in importance under the Trump administration and that the nation’s technology entrepreneurs were vital to national defense. Mattis paid his first official visit to the Pentagon’s Defense Innovation Experimental Unit, or DIUx, in Mountain View, California, as part of a two-day outreach tour to the U.S. technology industry intended to highlight the Pentagon’s commitment to technology innovation. “There is no doubt in my mind that DIUx will not only continue to exist, it will actually grow in its influence and its impact on the Department of Defense,” Mattis told reporters during brief remarks at the DIUx facility. DIUx was set up two years ago by Mattis’ predecessor, Ash Carter. It serves as a Pentagon hub for attracting private-sector innovation to solve complex and technical military challenges. But DIUx has faced criticism from some Republican lawmakers who have questioned its value and organization. The program underwent an overhaul in May 2016, less than a year after launching. Since June of last year DIUx has awarded $100 million in contracts for 45 pilot projects in areas including artificial intelligence, autonomous machines and space. The unit currently has 48 staff and is expected to grow to about 75 by the end of 2018, said Sean Singleton, DIUx’s director of engagement. Mattis said DIUx would help the U.S. military become “more lethal and more capable of defending our experiment that is called the United States of America.” The unit’s leadership was reporting directly to his senior staff, Mattis said, adding that he expected DIUx would help the military incorporate advances in artificial intelligence taking place in Silicon Valley. The defense secretary’s visit came as the Trump administration has sparred with the technology industry on a host of issues, including immigration, climate change and privacy. Earlier on Thursday Mattis visited Amazon’s headquarters in Seattle. He was expected to visit Alphabet’s Google headquarters in Palo Alto, California, on Friday. “A pleasure to host #SecDef James Mattis at Amazon HQ in Seattle today,” Amazon Chief Executive Jeff Bezos wrote on Twitter in a post that included a photo of him and Mattis smiling at one another.     