Presidents Joe Biden and Volodymyr Zelenskyy took their case for supporting Ukraine to the U.N. General Assembly last week, with Biden claiming Moscow believes the world will grow weary of the war and allow Russian forces to "brutalize Ukraine without consequence."

Biden spoke hours before Zelenskyy made his case, accusing Russia and President Vladimir Putin of not only using the threat of nuclear war to get their way but also weaponizing food, energy and the forced deportation of children.

Sean McFate, adjunct professor in Maxwell's Washington programs, says the U.N. mission of preventing and ending wars has "become a punchline," citing struggles in Iraq, Afghanistan, Syria, Zaire and Somalia and genocides in Rwanda, Darfur and Iraq.

"Bigger question," McFate says, "Will the UN be around in 2050? Only on letterhead."

Read more in the USA Today article, "'Evil cannot be trusted': Biden, Zelenskyy decry Russian aggression at UN."