The USSR starved a lot of people, not merely those in the territory of the Ukrainian SSR. Stalin exported their food to pay for his military industrialisation program, of which the focal point for investment was the Donbass. Nikita Khrushchev rose through the ranks of the CP-Ukraine and CP-SU during that time, and eventually succeeded his boss.
Definitely war-related, just as much as the artificial famine Japan caused in China and Vietnam.
Much more war-related than Suharto's massacres of ethnic Chinese and Leftists in peacetime, or Chiang Kai-shek's slaughter of, well, everybody not obeying him.
Mao, though, not the remotest external excuse there. He was asserting dominance over his military and politbureau, and it worked, but thankfully he died right after the "Three Difficult Years".