LONDON -- LONDON (AP) - The decision to leave the European Union divided the bloc and shattered the stability of British politics.

The country is set to install its seventh prime minister since the June 23, 2016 referendum, held a decade ago this Tuesday, when voters chose by 52 percent to 48 percent to depart the EU after more than 40 years of membership. Conservative leader David Cameron, who initiated the vote yet backed remaining, resigned immediately afterward.

Each of his successors has wrestled, mostly without success, with the fallout from that break. The current officeholder is Labour's Keir Starmer, who revealed on Monday his plan to resign following two years marked by weak growth, ineffective administration and a fractured, disillusioned public - outcomes tied in significant ways to the Brexit process.

Although the topic has slipped from daily coverage, the underlying effects of Brexit continue to shape the nation's fractious political scene, according to academic Chris Grey, who has tracked the consequences of the departure.

Those advocating exit assured voters that leaving the then-28-nation economic and political union would restore sovereignty over legislation, commerce and immigration.

While the stay campaign stressed economic risks, the leave arguments appealed more to emotion.

One prominent leave advocate, Boris Johnson, who later served as prime minister, declared weeks before the vote that the nation could glimpse brighter prospects ahead and should seize the historic opportunity.

University of Toronto emeritus history professor Margaret MacMillan noted that Brexit drew on several drivers, among them longing for a romanticized history, opposition to perceived open immigration, resistance to EU rules and a narrative of wartime isolation that overlooked allied contributions.

She added that the practical implications of departure were never spelled out clearly.

Soon afterward, the optimistic pledges of tighter border controls, fresh trade agreements, boosted public funding and simpler regulations ran into stubborn realities.

Lengthy and contentious negotiations stretched across years. Formal exit occurred on January 31, 2020, followed by an 11-month transition before full separation.

Cameron's successor, Theresa May, resigned in 2019 after repeated failures to secure parliamentary approval for exit terms.

Johnson took over, vowed to complete the process and delivered a minimal trade agreement that left relations with the EU strained. He was removed by his party in mid-2022 amid scandals. Liz Truss followed but lasted only 49 days. Rishi Sunak then improved ties modestly without major shifts.

Starmer pledged a fresh start yet declined to pursue reentry into the seamless single market free of tariffs and barriers.

As he departs, the Brexit settlement stays incomplete.

Historian Anthony Seldon observed that Cameron had hoped the referendum would settle long-running Conservative disputes over Europe. Instead, those fixated on the issue remain so, and national challenges persist, he told Times Radio.

During talks, pro-EU Conservatives favoring closer links were sidelined by the dominant leave faction.

Labour, generally more supportive of the EU, harbors its own split between those seeking closer ties or even return and leaders like Starmer who prefer to sidestep past divisions.

Ten years later, large numbers of voters have turned from the major parties toward options such as the Greens on the left and Nigel Farage's hard-right Reform UK.

Farage stands out as a chief beneficiary. He pushed for exit, later claimed it was mishandled and redirected his focus from EU workers to small-boat arrivals. His party now tops polls.

Economic performance has lagged over the decade as firms encountered fresh hurdles trading with nearby partners, though other factors including the pandemic, the Russia-Ukraine conflict and tensions in the Middle East also contributed to sluggish growth.

Throughout, politicians have avoided honest discussion with the public that tax restraint, debt limits and improved services cannot coexist, noted Hannah White of the Institute for Government.

This has left citizens frustrated.

Brexit did not calm immigration debates, which have grown sharper irrespective of actual figures. Net migration climbed past 900,000 in 2023 before dropping to 171,000 last year.

Disillusionment has risen and confidence in leaders has fallen. Recent agitators have stirred anti-immigration unrest after incidents involving migrants or false claims about them.

Britain once maintained a clear line separating mainstream debate from street violence, Grey noted. That line has weakened, and the shift traces in large measure to Brexit.

Surveys indicate some regret, with a recent Ipsos poll showing 52 percent favoring return to the EU against 33 percent opposed.

Hundreds marched in London on Saturday waving EU flags in support of rejoining, though turnout was modest compared with earlier protests. Many simply wish to move forward.

Yet Brexit remains a risky topic politicians avoid. Even with desire to return, the path would be lengthy and the EU cautious.

Grey warned that without willingness to confront the Brexit legacy, Britain faces ongoing low-level instability, likening the situation to a persistent ailment that drains vitality without prompting treatment because the remedy seems unpleasant.