A man waves a Union Jack and a European Union flag outside the Houses of Parliament at an anti-Brexit protest June 28 in London. (Justin Tallis/AFP/Getty Images)

Over the past week, countless political scientists and historians have weighed in on many aspects of the United Kingdom’s Brexit vote, here in the Monkey Cage and elsewhere, saying Britain’s vote on June 23 to leave the European Union is indeed a historical and rather unprecedented case.

Still, in many ways, Brexit isn’t all that special.

My in-progress research on exits from international organizations looks at why countries choose to withdraw. This research can offer a new way to look at the Brexit decision. In fact, in some ways, Brexit isn’t so very different from other decisions to withdraw from international organizations, also known as IOs.

The universe of IO withdrawals reveals four themes:

1. IO withdrawals are rare.

Since World War II, there have been more than 225 cases of member-state withdrawals from international organizations that are formed around issues as varied as whaling, labor standards and nuclear non-proliferation.

Here are some examples from the past five years. Gambia withdrew from the Commonwealth Secretariat, accusing it of being a “neo-colonial institution,” in 2013. Canada withdrew from the World Tourism Organization, which had appointed Robert Mugabe as a leader, also in 2013. And in 2010, Panama withdrew from the Central American Parliament because it considered the group “ineffective.”

Although such withdrawals have been relatively rare, they have become more frequent over time. This is partly because of the steady increase in the number of IOs themselves, as well as the ranks of member states joining these organizations.

Withdrawals tend to be rare because they are costly to both the withdrawer and the remaining states, as anyone knows who has seen the stock market volatility this past week. Indeed, that’s what makes Brexit so shocking.

2. States often stop short of withdrawing when other actions are effective.

Withdrawing from an international organization is just one way that a state can legally exit an international organization. Often international treaties have “flexibility devices” — including reservations, duration and amendment rules, escape clauses, dispute settlement mechanisms and so on.

These are designed to address states’ concerns before they must engage the proverbial “nuclear option.” Britain’s myriad special arrangements with the E.U. (including not having to join the euro zone) should be counted in this set.

Withdrawals are rare also because states often get what they want by threatening to withdraw. For example, Britain threatened to leave the European Economic Community (EEC) in 1975 (also by referendum) if the EEC heads of state did not agree to renegotiate the terms of British accession. While Britain struck a favorable deal in 1975, its threat of withdrawal this time around was not enough to garner its four desired E.U. reforms.

3. Geopolitically powerful states and pariahs are the most likely to withdraw.

While withdrawals are rare, existing research highlights that geopolitically powerful states or those that contribute disproportionately to the IO are the most likely to do so. They have strong go-it-alone potential and therefore higher bargaining leverage both within and outside the institution.

Pariah states also are more likely to withdraw, for several reasons. When pariahs no longer wish to adhere to their IO’s mandates (nor hear about their lack of compliance to international norms), they withdraw to maneuver without institutional constraints.

For example, the Democratic People’s Republic of Korea (DPRK) withdrew from the International Atomic Energy Agency (IAEA) in June 1994, arguing that the IAEA “jeopardized the supreme interests of the DPRK and flagrantly encroached upon its sovereign rights and dignity.”

Withdrawing can also be a last-ditch effort for a pariah state to salvage something of its reputation by challenging the international order. In 2003, for example, Zimbabwe preemptively quit the Commonwealth rather than being suspended after its elections were widely seen as flawed.

4. IO withdrawals often relate to domestic appeasement — or organizational failures.

States withdraw from international organizations as political tools to accomplish political goals. But the universe of IO withdrawals shows that there are distinct domestic and institutional politics at play.

First, and perhaps surprising, governments often withdraw from IOs as a way to placate domestic political pressures.

For example, news reports covering the United States withdrawal from the International Labor Organization (ILO) in 1977 cited President Jimmy Carter’s need for political support back home. By withdrawing from the ILO, he appeased labor (the AFL-CIO), business (the U.S. Chamber of Commerce), and the pro-Israeli lobby — all of which were needed to gain traction for his energy bill and the new Panama Canal treaties.

In this regard, again, Brexit is not an outlier. Why did the referendum take place? Back in 2014, Prime Minister David Cameron thought announcing this vote would help maximize Tory votes in the general election.

Second, states tend to withdraw from IOs to express displeasure in a malfunctioning or inefficient institution. This helps them push for changes in outcomes, both within and outside the IO.

The United Nations’ Industrial Development Organization (UNIDO) has been hit hard by withdrawals in recent years, for instance. In 2012, the U.K. withdrew from the organization after the U.K.’s 2011 Multilateral Aid Review concluded that there was no “evidence of UNIDO having a significant impact on global poverty.” Lithuania (2012), New Zealand (2013), France (2014) and Portugal (2014) quickly followed suit. The possibility of domino withdrawals is also currently worrying E.U. leaders.

Is Brexit an outlier, in the vast universe of international organizations and who belongs to them? Probably not.

That said, it is important to remember that the E.U. isn’t quite your ordinary IO. That’s, of course, also why this seems like a bigger deal. But putting the Brexit decision in context is important: It follows many of the same patterns that are present when we look at why states withdraw from IOs.

Nations — particularly the geopolitically powerful and pariahs — tend to use withdrawal to appease domestic political pressures as well push for institutional changes.

But looking across history, withdrawals have never been a “fast fix.” Instead, heads of state delay taking this extreme step, working hard on every other diplomatic strategy before exiting. And this is why Brexit — despite not being all that different from other IO withdrawals — has been so surprising to so many.

Felicity Vabulas is a postdoctoral lecturer at the University of Chicago’s Harris School of Public Policy.