As there is only one Russia, a comma is needed: Russia, which has attacked Ukraine, will lose the war. Who is wrong and that is not possible in a nondefining relative clause. The possessive/genitive form whose is always possible when the genitive is needed.
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As there is only one Russia, a comma is needed: Russia, which has attacked Ukraine, will lose the war.
Who is wrong and that is not possible in a nondefining relative clause. The possessive/genitive form whose is always possible when the genitive is needed.
Russia, whose army has attacked Ukraine, will lose the war.
Also: Russia, the arm