The poisoning of former Russian spy Sergei Skripal and his daughter in the English town of Salisbury is the work of the Russians. We know it, and when they bluster in denial, they are lying. This is not the first of their political murders. The time for proportional responses to Russia is over.

By one count, Skripal’s poisoning is the 15th death, or near-death, related to Russia in Britain since 2006 — and that doesn’t include the suspicious deaths in Skripal’s family. Most famously, defector Alexander Litvinenko was poisoned in London in 2006 with Polonium-210.

But there was also Scot Young, a friend of Russian exile Boris Berezovsky, who was impaled on an iron fence after a fall from a London window in 2014. There was Alexander Perepilichnyy, who died while jogging in 2012, and Berezovsky himself, found dead in his bathroom with a scarf around his neck.

The deaths don’t just happen in Britain. In 2015, a former aide of Vladimir Putin, Mikhail Lesin, died in a Washington, D.C., hotel room. Lesin’s death was called accidental, but, as The Washington Post notes, “officials never explained how he got the blunt force injuries to his head and body.”

I’m satisfied with the initial U.S. and British response to Skripal’s poisoning. The British expulsion of 23 Russian “undeclared intelligence agents” is good. I like the new U.S. sanctions on Russia, and the formal support the Trump administration has given the British.

And I like U.S. Ambassador to the United Nations Nikki Haley’s plain speaking in the Security Council. She’s right: Russia doesn’t just use chemical weapons in Britain. It also uses its council veto to shield Syrian dictator Bashar Assad’s use of chemical weapons.

But none of this goes nearly far enough. And here’s what I don’t like. I don’t like it when Robin Niblett, the director of the British think tank Chatham House, says: “I’m not sure there are a lot of clear options for the U.K. government on this.” Of course there are clear options.

And I don’t like it when NATO Secretary General Jens Stoltenberg says the West does “not want a new Cold War” and that our response to the Skripal attack should be “proportionate, measured and defensive.” Wrong. It should be disproportionate.

Isn’t it time to give this nonsense about not wanting a new Cold War a rest? This is a new Cold War. And isn’t it time for us to stop confessing our own powerlessness? The West isn’t powerless.

You want clear options? Here are a few. Put a resolution to the Security Council condemning Russia. They’ll veto it. Good: Force them to own their actions.

Stop pretending people fall out of windows by accident. Reinvestigate all the suspicious deaths. Name Russia as the guilty party. Impose stringent sanctions on Russian elites in the West, and confiscate the money they’ve stolen from the Russian people.

Ask Germany to cancel the Nord Stream 2 pipeline with Russia, which will only increase the West’s reliance on Russian energy. Accelerate the supply of U.S. natural gas to Europe.

Stop Russia from using Interpol to harass political opponents. This isn’t something that happens only in Europe: it’s going on in the United States.

Reinforce U.S. and British forces in Eastern Europe, and assign troops to NATO’s defense plans for the Baltics. If Germany and France get in the way, call them out in public. And state publicly that Vladimir Putin’s so-called re-election in Russia is a fraud and a farce.

We are not going to make an impression on Russia by being proportional. We must confront Russia with actions that impose disproportionate costs on their murderousness. If we do not establish credible deterrence against Russia, its assaults of the past decade will continue.