Britain's Prime Minister David Cameron (L) Russia's President Vladimir Putin (C partially obsured) and President Barack Obama arrive to pose for the family picture of the G8 summit at the Lough Erne resort near Enniskillen in Northern Ireland on June 18, 2013. (AFP/AFP/Getty Images)

I do not know what would have happened if, three years ago Monday, David Cameron, the British prime minister, had not foolishly held and lost a vote on intervention in Syria in the House of Commons. Perhaps if he had paid more attention, seemed more interested and told his colleagues to come home from vacation, he might have succeeded. Perhaps an intervention would have followed. Perhaps it would have helped end the conflict — or perhaps it would have failed.

We will never know. But we do know what happened instead. Britain withdrew support for a mission intended to halt the use of chemical weapons by Bashar al-Assad, the Syrian dictator. Spooked by the House of Commons vote, President Obama also changed his mind. On the morning of Aug. 30, 2013, Secretary of State John F. Kerry called for action: “History is full of leaders who have warned against inaction, indifference, and especially against silence when it mattered most.” By the next day, however, the president declared that all plans for a strike were off. The French, caught off guard, didn’t want to do anything alone, so they too withdrew — regretfully. “It was a great surprise,” the French prime minister told the Atlantic’s Jeffrey Goldberg. “If we had bombed as was planned, I think things would be different today.”

I repeat: Maybe a U.S.-British-French intervention would have ended in disaster. If so, we would today be mourning the consequences. But sometimes it’s important to mourn the consequences of nonintervention too. Three years on, we do know, after all, exactly what nonintervention has produced:

Deaths. Estimates of war casualties range from about 155,000 to 400,000, depending on who is counted. This month, the Syrian Observatory for Human Rights had registered a total of 14,711 dead children. Since the Islamic State created its caliphate in Syria, an estimated 2,350 civilians have been executed by the group. Life expectancy in Syria has dropped from almost 80 to 55.

Refugees. According to the U.N. High Commissioner for Refugees (UNHCR), there were 4.8 million registered Syrian refugees as of Aug. 16. There are thought to be an additional 2 million refugees who remain inside Syria but are displaced from their homes. Three-quarters of those who have fled their homes are women and children. Most own nothing except what they are wearing. To give some perspective, the refugee crisis caused by the Yugoslav wars in the early 1990s produced 2.3 million refugees, a number then considered to be the worst refugee crisis since the 1940s. The Syrian crisis is three times larger.

In a brief statement Sunday, Jan. 31, Secretary of State John Kerry called for the continuation of Syrian peace talks in Geneva and for immediate steps to increase food aid and other humanitarian assistance to Syrians. (U.S. Department of State)

Physical destruction. The ancient cities of Aleppo, Bosra and Palmyra are irreparably damaged. Damascus is badly damaged. Infrastructure — roads, bridges, factories — across the country has been destroyed. Schools and hospitals have been leveled. Only last month, the Syrian government bombed four makeshift hospitals and a blood bank in Aleppo.

Destabilization of the region. The vast majority of the refugees are in Turkey, Lebanon, Jordan, Iraq and Egypt, where they put an enormous economic and political burden on poorer, frailer states. A fifth of the residents of Lebanon are Syrian refugees, numbers that may upset the delicate political balance there. Riots have broken out in refugee camps in Jordan. In Turkey, the side effects of the Syrian war also include the exacerbation of tensions with the Kurdish minority and other groups inside the country, as well as high rates of crime, smuggling and unrest along the border. Turkey, a NATO member, has been drawn further into the conflict: If the Islamic State attacks Turkey, there may have to be a NATO response.

Destabilization of Europe. Thanks in part to the war in Syria, hundreds of thousands of refugees have sought to reach Europe by boat across the Mediterranean or by foot across the Balkans. UNHCR reckoned in May that more than 2,000 people — from Syria as well as Africa — had drowned in 2016 alone, more than had died in the same period in 2015. Islands off the coast of Greece and Italy are overwhelmed. The European Union’s unwillingness or inability to control the flow has helped further undermine its institutional credibility.

Rise of xenophobia across the West. The spectacle of hundreds of thousands of people walking and sailing into Europe has also launched an unprecedented wave of xenophobia. Elections in Austria and Poland have been partly swayed by anti-refugee rhetoric, which also played a part in the Brexit vote in the U.K. Far-right and nationalist parties in Hungary, France, Germany and Italy are successfully using fear of Syrian refugees to gain support. So is the Donald Trump campaign in the United States.

To sum up: Physical, human and political damage on an unprecedented scale; ongoing security threats; the renewed stirrings of fascism. Maybe those are better than the alternative that seemed so unpalatable to the British Parliament and the American president. But it’s hardly an outstanding success.

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