But they’’re not for the US alone, but I think they are also for our allies
From the U.S. Nuclear Weapons Budget: An Overview
The United States maintains a large and diverse nuclear arsenal to deter potential adversaries and to assure U.S. allies and other security partners.
The United States will spend at least $179 billion over the nine fiscal years of 2010-2018 on its nuclear arsenal, averaging $20 billion per year, with costs increasing from $16 billion to $25 billion per year over that timeframe.
This estimate by no means, however, includes the full costs of maintaining America's nuclear deterrent. The $179 billion includes most of the direct costs of nuclear weapons and strategic launchers, such as missiles and submarines, as well as a majority of the costs of military personnel responsible for maintaining, operating, and executing nuclear missions. This estimate, however, excludes many other essential functions directly related to nuclear operations, because those numbers are not readily identified in current budget documents. Moreover, these costs include no money for the eventual retirement of these systems, or support for veteran pensions or healthcare.
It may sound awful, but with other countries having Nuclear weapons, we need them.