The opening of the Berlin Wall in 1989. (CAROL GUZY/The Washington Post)
Opinion writer

Thirty years ago this month, the Soviet empire began to end. Officials from a new reform-minded communist Hungary and its democratic neighbor, Austria, dismantled the barbed-wire border fence that had separated them and deterred free movement of people from the Soviet-dominated East to the American-allied West.

Within weeks, East Germans were moving via Hungary to West Germany, a refugee exodus that Budapest welcomed and that would lead to the fall of the Berlin Wall and reunification of Germany.

What a distance the world, and the United States, has traveled since those heady and, for Americans, triumphant days.

As Europe threw off the communist yoke in 1989, it seemed not only a victory for U.S. power but also a vindication for U.S. political ideals and institutions. Nowadays, though, it seems that 1989 planted the seeds of instability in the United States, too.

The legitimacy crisis it fed in this country was not as direct or sudden, and not nearly as catastrophic, as the Soviet Union’s, but it is real just the same.

The Cold War contest with the Soviet Union provided a unifying theme not only to U.S. foreign policy but also to domestic politics. Facing a threat that was seemingly both eternal and mortal, American political leaders muted, compromised or, at times, suppressed their country’s internal conflicts — above all, those between the two parties — lest divisions render the United States vulnerable to the Soviets. There were many exceptions to this rule, of course, but generally, the vaunted “two-party system” kept a giant, diverse nation together through a long, twilight struggle.

Since the Soviet Union dissolved on Dec. 26, 1991, however, U.S. politics have gradually — and, in recent years, rapidly — reverted to something like the vicious zero-sum partisan game of the 19th century. The very idea of compromise has fallen into disrepute, scorned on all sides as a symptom of corruption, not consensus.

The terrorist attacks of Sept. 11, 2001, proved insufficient to rekindle a sense of national purpose even in the face of an external terrorist threat. To the contrary, the Iraq War and the 2008 financial crisis damaged the reputations of U.S. foreign policy and U.S.-style capitalism, respectively.

With “mainstream” ideology under siege, ideas once deemed too radical for consideration in Washington now receive a polite, often favorable, hearing within the two major parties: socialism for the Democrats; “America First” for the Republicans. These notions last enjoyed such currency in the 1930s.

Perhaps most extraordinary, and dangerous, is that politicians compete to delegitimize not just each other but also the system of which they are supposed to be stewards. President Trump and his opponents routinely portray each other as the authors, or beneficiaries, of conspiracies or rigged elections.

In so doing, they both shape and express public opinion. Though the causes of Americans’ suspicion toward the national government vary, most of them now lack basic confidence in it. Only 17 percent say they trust Washington to do the right thing most or all of the time, according to the Pew Research Center. That figure has not exceeded 25 percent since 2007 .

In hindsight, we can see that this legitimacy crisis was brewing even at a time when the Cold War still exerted a unifying force. As political analyst Bill Bishop, author of “The Big Sort,” has pointed out, nearly 8 in 10 Americans trusted the government in 1964, but that figure began to fall in 1965 — the year of military escalation in Vietnam, Great Society legislation, the Watts riots in Los Angeles and other watershed events — and has never recovered.

The end of the Cold War set loose sources of domestic discord, many of which, such as racial and gender inequalities, needed to be aired. Will the 2020 presidential election, already the subject of warnings that it could somehow be stolen or the results not respected, sharpen or ease America’s legitimacy crisis?

In declaring his candidacy for president, former vice president Joe Biden, a product of the old two-party system, sounded themes that were stunningly conciliatory today but would have been routine in 1973, when his Senate career began — such as his reference in Iowa to “my Republican friends in the House and Senate.”

The 76-year-old Biden’s implicit offer is a return to normalcy, after a four-year anger-fest led by Trump. Normalcy as Biden knew it may be past restoring, though; his message got a mixed reception from fellow Democrats. Political tribalism in the West has deep roots, both in human psychology and in public dissatisfaction with post-Cold War policy errors and unfulfilled promises.

June 2015 may go down in history as May 1989’s bookend. That month, Donald Trump declared for the presidency, and a new Hungarian government, led by former anti-Soviet activist Viktor Orban, announced plans for a razor-wire barrier across the country’s southern border, to block mostly Muslim refugees fleeing the Middle East. The two men meet at the White House on May 13.

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