ROME — Among the well-heeled bureaucrats of the European Union, it is an article of faith that the bloc always emerges stronger from a crisis. The idealistic founders who six decades ago dreamed of stitching warring nations into a peaceful whole knew the path would be bumpy. But always, the union wobbled forward.

Now the dream of an integrated and ever-stronger Europe could sink into the English Channel on Thursday, when British voters decide whether to abandon the bloc. To the pro-Europe establishment, this latest crisis is considered a peculiarly British affair, in which the villains are opportunistic politicians steering voters toward a delusional, self-inflicted mistake.

That may be. But if Britain does leave, the European Union can also blame its own handling of the crises of the past decade — the tribulations of the euro, the debt standoff with Greece and a flawed approach to migration. Each time, the bloc rammed through ugly, short-term fixes that only inflamed the angry nationalism now spreading across the Continent and Britain.

The result was almost a decade of ad hoc crisis management that even many admirers agree has left the European Union badly wounded and its reputation badly damaged. Idealism has given way to disillusionment. The bloc’s elite technocrats are often perceived as out of touch, while European institutions are not fully equipped to address problems like unemployment and economic stagnation. Political solidarity is dissolving into regional divisions of east and west, north and south.