Have US and Russia entered a new arms race?

The Donald Trump administration's first Nuclear Posture Review, presented in February, has abandoned former president Barack Obama's nuclear disarmament "promise" and, instead, vowed to enhance the role of nuclear power in the US' security strategy including developing sea-launched nuclear missiles, which in a way lowers the threshold for using nuclear weapons.

In March, Russian President Vladimir Putin announced that Russia has developed a new type of strategic weapon system comprising hypersonic missiles, nuclear power cruise missiles and unmanned underwater vehicles. This shows Moscow is prepared for a nuclear arms race with Washington.

US-Russia relations deteriorated following the Ukraine crisis, and further worsened due to allegations of Russia's involvement in the US presidential election. And now the Trump administration wants to "terminate" the Intermediate-Range Nuclear Forces Treaty signed by the United States and the Soviet Union three decades ago to eliminate all nuclear and conventional missiles and their launchers with ranges of 500-1,000 kilometers and 1,000-5,500 km - the treaty didn't cover sea-launched nuclear missiles, though.