What do liberal causes such as hate-crime laws and the London detention of former Chilean dictator Augusto Pinochet have in common with conservative causes such as the Defense of Marriage Act and harsh mandatory prison terms for drug offenders?

All of these measures are championed by politicians who hope to do well by making certain constituencies feel good. And all of these measures are likely to do nothing–or worse than nothing–for the people they purport to help. All of them have unhealthy side effects. And all, except for the Pinochet snatching, are embraced by President Clinton.

Feel-good politics is not new. But it seems ever more potent at a time when so many voters’ views on public issues come through the quarter-inch-deep medium of television–rather than through reading, reflection and reasoning–and when so many politicians shape their principles by poll results.

Take the current campaign to expand federal hate-crime laws to cover crimes motivated by homophobia. This was spurred by the understandable public desire to ”do something” to express outrage at the sadistic robbery-murder of Matthew Shepard, allegedly by two gay-bashing thugs, in Wyoming.

Largely lost in the noise–on television, at least–were three reasons for concluding that the proposed legislation was an irrational response to the murder: First, there is no evidence that even a single crime would be prevented by new hate-crime legislation. Existing laws are entirely adequate to punish those who murder and assault, whatever the motives; Shepard’s killers could get the death penalty under Wyoming law. And there is no evidence that state authorities anywhere, today, systematically condone crimes motivated by homophobia, as many once condoned crimes motivated by racism.

Second, the need for collective expressions of outrage can be (and has been) met by speeches, marches, services, vigils, congressional resolutions, and more. Indeed, the unprecedented display of public revulsion against the gay bashing symbolized by Matthew Shepard’s death signals a healthy trend toward tolerance.

Third, new hate-crime laws are not only unnecessary to further that trend but will have baleful side effects. They may even increase homophobia. Nothing so inflames the bigotry that still lurks in many minds as the perception that gay people seek special privileges.

As Bill Dobbs, a spokesman for the gay group QueerWatch, told The Washington Post, piling up extra penalties for crimes motivated by homophobia is ”a glib answer to a very big problem.” And it could backfire. ”People will point fingers and say, ‘You’re not better than us,’ ” Dobbs said. ”If I’m killed, my life is as valuable as anyone else’s.” Exactly.

Opinion writers in The Washington Post have pointed out other malignant side effects of hate-crime laws. An Oct. 14 editorial noted that such laws risk both ”federal intrusions into presumptively local matters and . . . blending punishable conduct with protected–if also detested–feelings and expressions.”

Civil libertarian Nat Hentoff argued that such laws can operate to circumvent constitutional protections against double jeopardy, by exposing defendants acquitted by state juries to federal prosecution for the same acts. Such laws can also enable unscrupulous prosecutors who lack proof that a crime was motivated by bigotry, or even that it was committed by the defendant, to inflame jurors by dredging up allegedly bigoted statements by the defendant from years before.

And an Oct. 18 ”Outlook” piece by Kimberly Potter–co- author (with James B. Jacobs) of Hate Crimes: Criminal Law & Identity Politics–stressed that ”targeting certain offender prejudices inevitably elevates the pain of some victims above others and creates a divisive competition among various groups to have their victimization recognized through special statutes. . . . (This makes) the losers–those not included in hate-crime laws–feel disparaged.”

But such arguments have not swayed many advocates of hate-crime laws, including that group of liberals who luxuriate in their hatred of those they call haters, and who deal more in impassioned rhetoric than in reasoned argument. An Oct. 13 New York Times editorial was representative. Stressing that Matthew Shepard had died ”in a state without a hate-crimes law” and noting that his accused killers would be tried for first-degree murder, it proceeded to a classic non sequitur: ”His death makes clear the need for hate-crime laws.”

This is not to suggest that liberals have a monopoly on the manufacture of bad feel-good laws. Conservatives produce their share too, sometimes with the help of a president whose endless opportunism easily stretches to encompass their most demagogic proposals. It’s striking that the same President Clinton who now touts the need to hit homophobic criminals with special penalties was seen chasing homophobic votes in 1996 by signing the Defense of Marriage Act, and then running ads about it on Christian talk radio.

The Defense of Marriage Act provides that gay couples cannot qualify for spousal benefits under such federal programs as Social Security and Medicaid, and that if any state licenses gay marriages, others can refuse to recognize them.

Pushed by conservative Republicans in 1996, the act’s real purpose was to gratify the feelings of those who see homosexuality as a sin or a sickness. Clinton’s then-press secretary, Mike McCurry, aptly called it ”gay-baiting.” Then Clinton signed it. He was watching the polls.

Clinton also noticed the polls showing that tough mandatory minimum prison sentences for drug offenders command strong public support. Strong, but dumb. Most drug kingpins don’t get caught, so the most dramatic impact of the draconian laws passed by Congress since 1986 has been to imprison for between five and 20 years, without parole, thousands of relatively small- time, nonviolent bit players in drug deals, including many who would not otherwise become career criminals.

This sentencing regime has managed to lock up a staggering number of kids from poor inner-city neighborhoods, while doing nothing to stop the drug trade that ravages those neighborhoods.

All this was already obvious when President Clinton took office in 1993. And Janet Reno initially sounded as though she understood it. But Clinton, anxious to avoid the ”soft on crime” label, became more Republican than Newt Gingrich in championing barbaric sentences. So did Reno, in a stunning sellout of her principles.

In the international arena, the politics (and jurisprudence) of gesture is exemplified by the British government’s arrest of the 82-year-old Pinochet, while he was hospitalized in London, on a warrant from a Spanish magistrate who wants him extradited to Spain. Pinochet would face trial there for murder, torture and other ”crimes against humanity” (including some against Spanish citizens) by his regime. A British court quashed the warrant on Oct. 28, but Pinochet was still being detained pending appeal.

In an ideal world, dedicated to the rule of law, Pinochet would be punished for any murders or other atrocities that he is proven to have ordered or condoned. But in the world we live in, no head of state who has stepped down voluntarily has ever been criminally sanctioned by another nation, particularly (as is the case with Pinochet) over the objections of his own country.

For good reason. Pinochet, like the former rulers of South Africa, surrendered power only after receiving assura nces that he would not be punished for what he and his regime had done. Other dictators will cling to power at all costs if they might otherwise be snatched and tried by any country that can get its hands on them.

Moreover, for Spain to punish Pinochet with an assist from Britain–while they and other nations do business with dictators like Fidel Castro and Jiang Zemin, and while deposed tyrants like Ethiopia’s Mengistu Haile Mariam and countless Eastern European Communists go untouched–smacks not of law but of a lawless double standard.

These concerns might be overridden by evidence implicating Pinochet in murders outside Chile, including the 1976 car bombing in Washington that killed Orlando Letelier and Ronni Karpen Moffitt. But consider the long-term threat of that logic to the United States, given the propensities of some nations and international bodies to accuse it and its leaders of crimes against humanity.

Spectacles such as the snatching of Pinochet, and the selling of hate-crime legislation, force me back on Winston Churchill’s defense of democracy as the worst form of government except for all the other ones. He said that in 1947. Before television.