A soldier with a bayonet stands guard at the Capitol on April 8, 1968. (Charles Harrity/AP)
Brian Rosenwald is one of the co-editors of Made by History, a fellow at the University of Pennsylvania and author of "Talk Radio's America."

Fifty years ago, a few days encapsulated all the tumult and trends that made the late 1960s so fractious.

On Sunday, March 31, 1968, President Lyndon B. Johnson stunned Americans by announcing that he would not run for another term. Johnson had accumulated landmark achievements, including Medicare, Medicaid, the Civil Rights Act and the Voting Rights Acts. But his political fate was sealed by a surge in crime, multiple summers of urban riots and a deeply divisive quagmire of a war. Vietnam not only starved his beloved Great Society of federal money — it also fueled a credibility gap that eroded Americans’ faith in government, souring voters on liberal activist policies for more than a generation. Without trust in government, Americans weren’t interested in big new social programs.

Four days later, an assassin’s bullet felled Martin Luther King Jr. in Memphis. In Indianapolis that night, a stirring speech from presidential candidate Robert Kennedy may have prevented the city from exploding in riots. Two months later, though, Kennedy too would be dead, assassinated like his brother and King. The murders dashed the hopefulness that figures like King and the Kennedys had stirred earlier in the decade.

In more than 100 other cities, riots did erupt after King’s assassination, an expression of the frustration and fury felt by many Americans who lived in squalid ghettos with minimal opportunities, thanks to institutional racism and government policies that discriminated against African Americans. For others, however, the riots reinforced the sense that the country was spinning out of control and that only a heavy hand toward rioters, demonstrators and criminals — no more attempts to address their grievances — would restore peace and prosperity.

This dichotomy would shape the politics of the next half-century. To many inner-city African Americans and their allies, the Civil Rights Act, the Voting Rights Acts and the Fair Housing Act, which would become law a week after King’s assassination, didn’t go far enough to fight the effects of centuries of pervasive racism. Yet many white Americans — conservatives and liberals alike — felt that the wrongs of segregation had been corrected, and they had little desire to sacrifice to enact further remedies.

The rest of 1968 would continue to be tragic and chaotic. But these few short days had already demonstrated the forces reshaping American society and politics. The fissures revealed remain a dominant force in politics today.

Twitter: @brianros1

Sunday, March 30. President Lyndon Johnson works on a speech in the White House. He announced the next day that he would not seek or accept the nomination for reelection. (BOB DAUGHERTY/AP Photo)

Wednesday, April 3. The Rev. Martin Luther King Jr. at the Lorraine Motel in Memphis. The following day, the civil rights leader would be shot dead on a balcony at the hotel. (Charles Kelly/AP Photo)

Saturday, April 6. Children pass King’s casket in Atlanta. The murder sparked riots in more than 100 cities, adding to a sense among some Americans that the country was out of control. (Horace Cort/AP Photo)

Sunday, April 7. Robert Kennedy walks down 14th Street NW near Columbia Road in Washington, an area devastated by riots. Two months later, he would be assassinated. (AP/AP Photo)

Monday, April 8. Soldiers serving in Danang, Vietnam, attend a memorial service for King, who had opposed the conflict. By this time, public opinion in the United States was turning against the war. (Eddie Adams/AP Photo)

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