USD became strong against EUR, CNY, INR, JPY, GBP during the war time when compared values of pre-war date Feb-24-2022 and current war date Mar-22-2022 and reason could be USA is crude oil net exporter and defence equipment net exporter.
Crude Oil prices increases is a positive factor USA economy as USA is net crude oil exporter. USA Crude oil exports is more than Crude oil imports.
EUR is Europe currency. CNY is China currency. JPY is Japan currency. INR is India currency.
So whenever war happens between countries, the probability for USD to become strong is high.