Russia has announced it will stop abiding by the now-defunct INF treaty with the United States.

The announcement came just days after Trump ordered the repositioning of two nuclear submarines in response to what he called "threatening comments" from former Russian President Dmitry Medvedev, now deputy chair of Russia's security council.

Is this the beginning of a new nuclear arms race? What happens when nuclear posturing, once considered a taboo topic, plays out over social media between world leaders? And eighty years after Hiroshima and Nagasaki, have we forgotten the reality of nuclear war and the moral restraint that once held it at bay?

Host Zhao Ying is joined by Kamal Makili-Aliyev, Associate Professor at the School of Global Studies, University of Gothenburg, Joseph Siracusa, Professor of Global Futures, Curtin University in Australia, Zhang Xin, Deputy Director of the Center for Russian Studies at East China Normal University.