The policy would be a landmark change in the U.S. nuclear posture.

https://www.washingtonpost.com/opinions/global-opinions/allies-unite-to-block-an-obama-legacy/2016/08/14/cdb8d8e4-60b9-11e6-8e45-477372e89d78_story.html?utm_term=.ee9fd9c0882b