The catnip in Margaret Thatcher's win, for a lot of American voters, is what it might promise for Ronald Reagan if he runs again. The parallels between what Thatcherism and Reaganism have done for, or to, their countries are intriguing. There is the same shared interest in extreme free-market theory, though the common denominator is a remarkably similar anti-government talk. In both cases, it's more bark than bite. As Reagan raised California taxes and now ratifies the New Deal, so Thatcher as education minister under Edward Heath was regarded as a big spender. She vigorously executed many of the Labor plans she inherited.

The real affinity, politically, lies in the signal both Thatcher and Reagan send to the middle-middle class voters as both attempt to revive the spirit of independence and self-reliance. Thatcher and Reagan have restored to Anglo-American politics an almost innocent faith in the rewards of striving.

People on their left have, I think, underestimated the allure of the message. They have failed to grasp how soured middling voters are by the patronizing ideology of the welfare state. Not--it must be said emphatically --the welfare state itself. That is a fixture in which the middle-class stake on both sides of the Atlantic is now enormous. What voters seem to reject is being constantly preached at on the inevitability and even sanctity of the mothering state. That is true whether the preaching is paternalistic Toryism, socialist, or (as with East-Coast Republicanism or among some liberal Democrats) elitist. Voters accept that the state's helping hand is here to stay. But they don't like to be reminded every day. They don't like to hear that the age of self- help, like the frontier and the colonies, is closed.

In her free-market gab, as in her curt handling of the "wets" (the Tory paternalists), Thatcher has thrown over a long Conservative tradition. Harold Macmillan, a Tory traditionalist, has said he finds Thatcherism rootless and "suburban." In some ways it embodies the fear once expressed by Winston Churchill: that the Tory party, which Disraeli idealized as a romantic alliance of aristocracy and people, might become "rigid, secular and materialistic," like, he said, the American GOP.

It's hard to imagine Thatcher writing a passage like the one in "My Early Life" in which Churchill rejoices in the Tory welfarism that eased the old age of his devoted nurse, Mrs. Everest. Thatcher and Reagan, surrounded and influenced by their self-made entrepreneurial friends, are far removed from the Tory view of the state as common weal, as provider and protector. Their talk rings a bell with millions who reject the ethos, if not the fact, of the modern beehive life.

For those on either side of the Atlantic who take a less negative view of government, Thatcherism and Reaganism seem arid and rootless. Both the prime minister and the president seem to identify the state with statism, an elementary error. But Thatcher's victory leaves no doubt that this is powerful medicine, and it will be surprising if any of Reagan's challengers assail this politically profitable confusion.