US to up N-ante to curb Russia-China 'axis'

The strategy, President Donald Trump said, is tailored and flexible to address the wide array of threats in the 21st century.

"It pursues modernisation of our nuclear command, control, and communications, all three legs of our triad, our dual capable aircraft, and our nuclear infrastructure," said Trump after the the 2018 Nuclear Posture Review (NPR) was out at the Pentagon.

The strategy develops capabilities aimed at making use of nuclear weapons less likely, he said, adding that it enhances deterrence of strategic attacks against the US, its allies and partners, that may not come in the form of nuclear weapons.

"And, importantly, it reaffirms our commitment to arms control and nuclear non-proliferation, maintains the moratorium on nuclear testing, and commits to improving efforts to prevent, detect, and respond to nuclear terrorism," Trump said.

In his preface to the new policy, that runs into 100 pages, Defence Secretary Jim Mattis said maintaining an effective nuclear deterrent is much less expensive than fighting a war that the US was unable to deter.

"While we will be relentless in ensuring our nuclear capabilities are effective, the US is not turning away from its long-held arms control, non-proliferation, and nuclear security objectives," Mattis said.

"Our commitment to the goals of the treaty on the Non- Proliferation of Nuclear Weapons (NPT) remains strong," he said. Mattis said Russia and China are pursuing entirely new nuclear capabilities tailored to achieve particular national security objectives while also modernising its conventional military, challenging traditional US military superiority.