Due to the moratorium on actually testing the nukes by setting them off, some other means of testing the physics involved is needed to predict how the current warheads behave as they age.
This is a super explicit part of all the NIF press releases, and these "stewardship" experiments is what they were doing most of the time last year and. Here's a quote from the LLNL press release as an illustrative example:
“This result is a historic step forward for inertial confinement fusion research, opening a fundamentally new regime for exploration and the advancement of our critical national security missions. It is also a testament to the innovation, ingenuity, commitment and grit of this team and the many researchers in this field over the decades who have steadfastly pursued this goal,” said LLNL Director Kim Budil.
This is a super explicit part of all the NIF press releases, and these "stewardship" experiments is what they were doing most of the time last year and. Here's a quote from the LLNL press release as an illustrative example:
“This result is a historic step forward for inertial confinement fusion research, opening a fundamentally new regime for exploration and the advancement of our critical national security missions. It is also a testament to the innovation, ingenuity, commitment and grit of this team and the many researchers in this field over the decades who have steadfastly pursued this goal,” said LLNL Director Kim Budil.