Should the U.S. and NATO use military forces to defend Ukraine from a Russian invasion?

In early 2022 the Russian military built up a force fighter jets, air defense systems and 100,000 troops along its border with Ukraine. Military experts say the buildup gives the Russian military an array of options including seizing the entire territory or certain parts within the country. Ukraine was part of the Soviet Union before it collapsed at the end of the Cold War in 1991. The disintegration of the Soviet Union left Russia with a vastly depleted population, territory, and economy. Now Russian President Vladimir Putin is seeking to reclaim some of that glory …  ;and undo some of what Russia lost in the Cold War. He has described Russians and Ukrainians as “one people, a single whole.” In response to the Russian military buildup NATO deployed jet fighters and ships to the eastern border. The U.S. ordered 10,000 troops to be on standby in Europe. Ukraine isn’t a member of NATO but is a “partner country” to the military alliance. NATO has agreements in place that could lead Ukraine to join as member in the future.