The approval of additional troops comes in response to a request from U.S. Central Command.
Acting Defense Secretary Patrick Shanahan released a statement:
In response to a request from the US Central Command for additional forces, and with the advice of the Chairman of the Joint Chiefs of Staff and in consultation with the White House, I have authorized approximately 1,000 additional troops for defensive purposes to address air, naval, and ground-based threats in the Middle East.
The recent Iranian attacks validate the reliable, credible intelligence we have received on hostile behavior by Iranian forces and their proxy groups that threaten United States personnel and interests across the region.
The United States does not seek conflict with Iran. The action today is being taken to ensure the safety and welfare of our military personnel working throughout the region and to protect our national interests. We will continue to monitor the situation diligently and make adjustments to force levels as necessary given intelligence reporting and credible threats.