Conventional ICBMs are being considered under the Prompt Global Strike project [1].  From the summary:<p>&gt;  Conventional prompt global strike (CPGS) weapons would allow the United States to strike targets anywhere on Earth in as little as an hour. This capability may bolster U.S. efforts to deter and defeat adversaries by allowing the United States to attack high-value targets or “fleeting targets” at the start of or during a conflict.<p>&gt;  Some analysts, however, have raised concerns about the possibility that U.S. adversaries might misinterpret the launch of a missile with conventional warheads and conclude that the missiles carry nuclear weapons.<p>[1] <a href="https:&#x2F;&#x2F;www.fas.org&#x2F;sgp&#x2F;crs&#x2F;nuke&#x2F;R41464.pdf" rel="nofollow">https:&#x2F;&#x2F;www.fas.org&#x2F;sgp&#x2F;crs&#x2F;nuke&#x2F;R41464.pdf</a>