There is currently a high possibility of a Russian war against Ukraine, that might even threaten Poland and the Baltics. Further, military actions and protests in Kazakhstan raise the possibility of losing safe use of the Baikonur Cosmodrome by Russian cosmonauts and Progress cargo flights for some period of time.
Therefore, it would be wise for NASA Administrator Bill Nelson and Deputy Administrator Pam Melroy to develop or update contingency plans to continue to operate ISS, the International Space Station in the event of any possible loss of cooperation by Roscosmos, or during a temporary Russian loss of access to Baikonur.
If there are existing contingency plans, perhaps any developed at the time of the 2014 Russian invasion of Ukraine--when Russia actually did threaten to deny US crew from launching on Soyuz--then the sole crew transport to ISS, they should be updated to include the capabilities of SpaceX's Dragon, Northrup Grumman's Cygnus and Boeing's forthcoming Starliner for crew transport and reboosting.
By themselves, contingency plans could help deter a Russian leap to war, as one bit of leverage the Kremlin may threaten to encourage U.S. acquiescence to Russian military goals in Ukraine could be to obstruct the continued operation or survival of ISS. If ISS can survive without Russian systems, then they only 'spite themselves,' and would look weak while we continue operating ISS in their absence.
There are of course a great many contingency plans for every possible emergency on ISS. NASA and other international partners have a responsibility to add or update such plans to assure continuity of operations no matter what happens in the coming months in Ukraine.