Neither Reagan nor Thatcher were followed by Clinton or Blair

I know more about US politics than UK politics, but I know enough about both to answer. It was largely, but not entirely, coincidence.

During the Reagan/Bush 1 years, many people really thought that the US would keep electing Republican presidents for the foreseeable future. In 1968, Nixon is elected, and re-elected in '72. In the aftermath of Watergate, Jimmy Carter wins one term in '76. Then, Reagan wins '80 and '84, and Bush 1 in '88. So that's a full twenty year span with only one elected Democratic president. There were a variety of reasons for this. First, there was considerable anger at LBJ for not only the Vietnam War, but also the Civil Rights movements and Great Society programs, which many Americans did not agree with. Second, while we might think of politics today as polarizing, there were dozens and dozens of political bombings in the US in the 1960's and 1970's. Rapid cultural changes and the concomitant instability led to the rise of "law and order" politics. During the 1968 riots after MLK's death, LBJ brought in extra forces to make sure the White House was not stormed. The Weathermen were blowing buildings, and occasionally people, to smithereens. While the UK was not anywhere near as extreme as the US in that regard, transatlantic anger at people on the fringes of left politics really did make an impact.

New ideas about economics played a major role as well. Sluggish economies in the US and the UK (they were sluggish for related, but different reasons) played a role in convincing voters that it was time for a change. In fact, Carter had actually begun to implement some of the changes in economic policy that Maggie and Ronnie are famous for, but that's a discussion for another post.

One thing to remember is that Clinton won the 1992 election mostly because of Ross Perot as a spoiler candidate. Throughout most of HW Bush's term, people thought he would win again. But Perot won 18.9% of the vote, most of which probably would have gone to HW Bush, giving him a substantial victory. It's quite rare for Presidents to lose elections after winning wars. So Clinton won in '92 largely due to a spoiler candidate, which is obviously unrelated to the politics of the UK.

In the UK, Third Way politics were mostly a departure from the actual socialist policies that had previously been espoused, including things like nationalized industries. Tony Blair's politics embraced entrepreneurship and the free market, while providing a large social safety net, rather than simply socializing resources. In America, the democratic party hadn't been particularly socialist, so they couldn't depart from that, although Clinton did engage in welfare reform.

Politics does tend to work like a pendulum and in that sense it is a coincidence that America and Britain both swung from centre-right to centre-left parties at roughly the same time. That said, since Clinton and Blair, the two political scenes have diverged considerabley, suggesting more than mere coincidence.

Intellectually they both developed from the same source - the so called "third way" that was influential throughout the western world, but Clinton and Blair are perhaps it's most significant leaders.

Historically, UK and USA politics have influenced each other enormously. Clinton's Democratic party served as model for Blair's New Labour. Although Labour had since 1983 been approaching a more centrist position in policy terms, Blair borrowed heavily from Clinton in terms of electoral strategy, presentation, and PR.

As Blair says to Clinton, "you showed the way".

I'd recommended looking at the transcripts of their conversations that Clinton published: https://clinton.presidentiallibraries.us › files