Welcome to Hard Talk on the BBC World Service with me, Stephen Saka.

My guest today is serving his third term in the US Senate and has become one of the Democratic Party's influential voices on national security, not least because he chairs the Senate Intelligence Committee and is one of the handful of politicians on Capitol Hill given access to classified intelligence.

Right now, that means Senator Mark Warner's focus is on the Ukraine war and the massive U.S. government effort to ensure that Vladimir Putin's invasion strategy fails.

The Biden administration has ramped up military

and economic support for Ukraine while imposing unprecedented sanctions on Russia. In Moscow,

they accuse the U.S. of spearheading an expansionist NATO project to undermine Russian security.

It feels like the hostility of the Cold War has returned,

but with added unpredictability, not least when it comes to the possible use of nuclear weapons.

And all of this, while America's national security doctrine is increasingly preoccupied with the

long-term economic and military threat posed by China

and at a time when America's internal political polarization appears to be undermining faith

in the country's democratic institutions. So is America in any fit state to meet the challenges

it faces abroad and at home.

Well, Senator Mark Warner joins me now.

Welcome to Hard Talk.

Thank you so much.

Is there an attitude in this city, Washington, D.C.,

that you politicians are now prepared to do whatever it takes

to ensure Ukraine's victory in the war with Vladimir Putin.

Well, my sense, Stephen, is that this is not only an attitude that's reflected by politicians,

by the American public, quite honestly, I think it is the British government, the British public.

What has taken place over the last few months is the West NATO have come back together.

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