The United States of America is, in an ambient sense, a center-right capitalist country. Ronald Reagan claimed landslide victories (esp. in 1984 against Walter Mondale) by selling a generally sunny message about America's future, along with tax cuts, slashing red tape, strong national defense, tough-on-crime, all that good ol' traditional conservative stuff.
After Reagan left the scene, and the USSR collapsed, the Republican Party of the '90s found itself both without a charismatic leader and without a looming existential threat. It was at this point that Republicans got taken over by the Pat Buchanans, Newt Gingriches, and Rush Limbaughs of the world that preached grievance politics and perpetual culture war against "the Left." The curdling of the GOP base into a stew of rage and conspiracy-mongering began long before Trump, but his rise put an exclamation point on it.
The endurance of conservative religiosity and bootstraps anti-government attitudes guarantees a solid base for Republicans, especially in rural strongholds, but it's unlikely that the GOP's current combative and hysterical positioning will win over a majority of Americans any time soon, let alone with the kind of landslides that Reagan enjoyed.