Traumas suffered by a society generations ago can still have a negative effect centuries later.
This is something Americans of a certain age should have no difficulty understanding. Half a century ago, we had to grapple with a dysfunctional and unjustifiable system of legally imposed racial segregation. It was a legacy of the Civil War a century before and of slavery before that.
Americans managed to reform that system, but it wasn't easy. Getting rid of policies that are the responses to long-ago traumas is a difficult business.
Two current instances, one facing America and the other facing Europe, come to mind. Both result from strong desires to learn from the mistakes made in the years following World War I -- the Great War, as it was called at the time -- which began nearly a century ago.
The first case involves American immigration policy. Many Americans were uneasy about the millions of immigrants who had flowed in from Eastern and Southern Europe in the years after the opening of Ellis Island in 1892. World War I showed them that government could control the flow of people, and in 1924, Congress cut off the flow of Ellis Islanders.
This came to seem an injustice, especially to their descendants, and in 1965, Congress rewrote immigration law to allow large-scale low-skill and family-reunification migration. It was an attempt to atone for a mistake made in the wake of war.
But like most reforms, it had unintended consequences. Large-scale immigration came not from Europe, as expected, but from Latin America, especially Mexico, and also from Asia. The United States failed to keep illegal immigrants from crossing the land border with Mexico, and Congress rejected a national identity card that might have prevented illegals from getting jobs. By 2007, we had 12 million immigrants, and the controversy over what to do about them frustrated attempts to rationalize immigration law.
Now some illegals are returning home, but we still have a system that favors extended-family reunification over the high-skill immigrants whom Canada and Australia have been favoring for years. Decisions made years ago leave us with a dysfunctional immigration system.
Europe's historic problems and current plight are worse than ours. The extremist nationalism that led to the two world wars left postwar reformers like Jean Monnet convinced that European unity was necessary to prevent a third.