Joe Biden has reacted well to the Ukraine crisis, but the ball is now in Vladimir Putin’s court

In recent months Russia has amassed more than 100,000 troops on the country’s border with Ukraine, prompting fears of an invasion in the US and among European NATO allies. LSE US Centre Director Professor Peter Trubowitz looks at what Russian President Vladimir Putin wants to gain from the crisis, how President Biden has reacted to it, and what may happen next.