Q.Why should we Jews worldwide daven for the welfare of Ukraine? Ukraine has historically acted terribly (to put it mildly) against the Jews and perhaps this is HaShem's way of deservedly settling the account, Kein Yovdu Kol Oy'vei Am Yisroel.
A. Since according to the European Jewish Congress, as of 2014, there are 360,000–400,000 Jews in Ukraine, the tefilos are mainly directed for them and for the Chasidei Umos Haolam that protect them, or share with them and are also suffering.
Horav Shlomo Miller's Shlit'a opinion is that this crisis is one more warning from Hashem to all humans, that we are living in a world where things can change swiftly and catastrophically for all, if we don't all better our ways and behavior.
Rabbi A. Bartfeld as revised by Horav Shlomo Miller, Horav Dovid Pam, Horav Aharon Miller and Horav Chanoch Ehrentreu Shlit'a