One thing that is possible in the event of a war is relocation of the talent in neighboring countries. A small case in point - in Bulgaria there is a small but growing number of Turkish people in the IT. The ones I have talked with don't like the political situation in Turkey.
Which war? Russia will invade and annect the Donbass, as they did with the Krim, and dozens of times before with most of their neighbors. There will be an election and the Russian majority in the Donbass will agree to the "friendly" annection.
Kiev and the SW industry will stay unaffected, and there's no SW industry in the Donbass, only coalmines.
And actually the war there goes on since 2014. Russian "terrorists" invaded the Luhansk and Donjezk oblasts already and got rid of most of the Ukrainians there. Now it looks like they'll want Mariupol also. https://en.m.wikipedia.org/wiki/Russo-Ukrainian_War
the biggest I can think of is for companies that outsource to Ukraine. Other than that I dont really see this conflict affecting software industry in the USA. Maybe cyberattacks incidents increase.