Cheap demagoguery and policies based on tabloid emotionalism make for bad – even dangerous foreign policy. The progress of what's known as "the Magnitsky Bill" through Congress is a classic example of this.

In order for enough Republican and Democratic congressman to pose in their ignorance as “tough” they are enraging the public and leadership of a thermonuclear superpower (with 500 more warheads than the United States has, according to the Federation of American Scientists Nuclear Information Project.) and badly hurting the prospects for American business.

The Magnitsky Bill will heavily penalize Russia and Russian nationals for the death, in custody, in St Petersburg of Sergei Magnitsky – a lawyer for Hermitage Capital who had accused police and tax officials of embezzling $230 million.

He was found dead in his cell in highly suspicious circumstances. An independent investigation by the Kremlin’s own Human Rights Council concluded that he had in effect been murdered – that he had died of his injuries after being beaten by prison guards.

A doctor in the jail is currently facing a charge of negligence connected with Magnitsky’s death. And the State Department has already banned several dozen Russian individuals whom, it said, were implicated in it. These moves angered the Russian government, which has responded by barring several US officials in its turn from entering Russia.

Even this response, largely taken by the Obama administration in a vain bid to head off the imposition of far tougher congressional measures aimed at Russia, was a dangerous piece of over-reaction.

But the Magnitsky Bill is vastly more dangerous.

At a time when the United States is financially weaker and more militarily over-extended around the world than it has been for 40 years, this legislation could help turn Russia, a potential hugely important and constructive partner for the United States, into a dire enemy.

When the administration of President George W. Bush was under worldwide international criticism over the exposure of the torture and human rights abuses at the Abu Ghraib prison in Iraq, there were even efforts to indict senior U.S. officials of war crimes at the International Court of Justice at The Hague. At that time, the government of Russia wisely took no part in these efforts. They didn’t mess with our security concerns.

The facts of Magnitsky’s death are not in serious dispute. What happened to him was ugly and should certainly be condemned. But unfortunately, it was far from unprecedented. Suspicious deaths from brutality, conspiracy, for revenge or to shut up inconvenient witnesses are common in jails throughout the world, and they are not exactly unknown within this country either.

The fact of widespread corruption with post-communist Russian society is unfortunately all too real as well. But for the United States to penalize Russia for suffering from corruption would be like Captain Renault in the movie "Casablanca" professing that he was “Shocked! Shocked” to find gambling going on in Rick’s Café American, right before shamelessly stuffing his own winning at the roulette wheel into his own pocket.

For more than 30 years, the United States’ two most enduring and important allies in the Developing World were the nations of Zaire and Indonesia, both of which were being bled white throughout that time by the shameless, unrelenting kleptocracies of Presidents Sese Seko Mobutu in Zaire and Sukarno in Indonesia. Another of our long-time allies, President Ferdinand Marcos, was almost as bad.

Yet no Congress during all that time ever contemplated any legislation as harsh as the Magnitsky Bill against any of them. We held our collective noses and did business with them because it was in our interests to do so.

The current government of Russia, whether under new President Vladimir Putin or his immediate predecessor Dmitri Medvedev, has not been remotely in the Mobutu, Sukarno or Marcos class when it comes to corruption. The record of the Kremlin in cleaning up corruption is far from ideal, to put it mildly: But it is a lot better than virtually every government in the Developing World and it certainly does not warrant being singled out for sanctions by the Magnitsky Bill.

It is not as if the Russian government took no action over the death of Magnitsky: Then-President Medvedev replaced four Interior Ministry generals involved with the case.

Why then, the extraordinary over-reaction in Congress in pushing ahead with the Magnitsky Bill?For the US government does not the need additional powers of the Magnitsky Bill to prevent dubious businessmen or government officials from other countries entering this country. -- The State Department already has the full authority to deny visa to anyone they want without getting Senate resolutions.

No one is disputing the fact that those who denied medical attention to Magnitsky have to be punished. But by attaching the name of Magnitsky to its bill, Congress is making a fool of itself and doing no good for American business or real interests at all.

No one dreams for a second that the Russians will play nice if or when the Magnitsky bill becomes law. On the contrary, it is guaranteed to make them much nastier. How on earth is that going to be good for the American people and their economic and security interests?

Conservatives like to think they think and act more clearly and realistically than liberals. This is another time to prove it.

Martin Sieff is a former senior foreign correspondent for The Washington Times and former Managing Editor, International Affairs for United Press International. Mr. Sieff is the author of  "That Should Still Be Us: How Thomas Friedman's Flat World Myths Are Keeping Us Flat on Our Backs" (Wiley 2012) and "The Politically Incorrect Guide to the Middle East" (Regnery, 2008). He has received three Pulitzer Prize nominations for international reporting.