The Week summarizes a few important points from Ambassador Nicholas Burns on the Political Wire podcast :  

We’re not quite back into a Cold War, even if it seems as if we are. The media has continually suggested that America and Russia may have re-entered the Cold War in the wake of the Ukraine crisis. But the U.S. isn’t in a protracted state of nuclear tensions with a communist superpower anymore. So it’s a stretch to say that Cold War is back. But Burns said there are some echoes of it: “President Putin has used brute force to take over a piece of territory that wasn’t his. And he’s drawn new lines in Europe, so it feels a little bit like the Cold War that I remember back in the 1970s and 1980s,” even though we haven’t actually reached true Cold War status.  

Trust is key in foreign relations. Putin’s actions have shattered that trust for a long time. Trust “doesn’t mean you agree one everything, but it means that when some leader tells you something that he or she is going to commit to do something for you that it’s going to happen,” Burns said. Even though there was a modicum of trust between the U.S. and Putin after 9/11, that trust was damaged when Russia didn’t follow up faithfully on its promise to work closely with the U.S., Burns lamented. Now, with the Ukraine crisis, that trust may never come back as long as Putin is in power. “How can you trust a leader now, like Vladimir Putin, who invades another country and then formally annexes it?” Burns said. “We haven’t seen this kind of blatant, brazen behavior since the 1930s in Europe.” The loss of trust between the two nations could imperil their ability to work together on other high-profile matters such the economy and nuclear security.  

Listen to the whole thing: