On February 20, 2020, US Secretary of Defense Mark Esper participated in a military simulation exercise at the headquarters of US Strategic Command (STRATCOM) in Omaha, Nebraska. The classified exercise "simulated a 'limited' nuclear exchange with Russia" upon the launch of a Russian attack on a US target in Europe, and Esper acted in his own capacity as Secretary of Defense alongside other officials roleplaying the scenario. The US military conducts exercises in this vein fairly regularly in order to practice warfare mechanics and simulate potential crises, but Pentagon officials surprised journalists with their announcement of the exercise and certain details only a day later.
In the simulation, Russia launched a low-yield, limited nuclear weapon against an unknown site within NATO territory, and the US defense secretary (Esper) and president chose to retaliate by way of 'limited response'. Officials did not specify what qualified as 'limited', but it could suggest a number of options, including:
- a small number of nuclear weapons
- an existing low-yield nuclear weapon in US arsenal
- the W76-2 warhead (attached to a submarine-launched ballistic missile (SLBM))
The latter warhead was first deployed to a submarine patrolling the Atlantic Ocean near the end of 2019--made public in January of this year--and constitutes a big step in the Trump administration's efforts to modernize the US's nuclear triad system and current stockpile. Given the nuclear threats already posed by Russia, China, and North Korea, and the potential threat of an Iran-gone-nuclear, many US military personnel see such steps as crucial to maintaining American superiority and preventing nuclear war.