After electing and re-electing a black man as President, America's younger generation is unaware of how vicious segregation was in King's day. This week marks the 50th anniversary of the release of King's "Letter from a Birmingham City Jail." He was arrested for leading demonstrations to desegregate Birmingham, without a permit.

While sitting in his cell he was given a copy of a "Call for Unity" by five white Episcopal Methodist and Catholic bishops, and a leading Baptist, Presbyterian and Jew. They attacked the civil rights campaign as "unwise and untimely," and a provocation to hatred and violence.

They denounced "outsiders coming in," and urged restraint and appealed to "white and Negro citizenry to observe the principles of law and order." In a controlled fury, King crafted a letter of reply ostensibly addressed to the eight clergymen, but targeted at white moderates and President Kennedy.

It was a "powerful indictment of the shortcomings of timid moderation in the face of injustice, a sermon of chastisement - a shrewd, tough-minded, even militant political comment," writes Robert Westbrook in this week's "Christian Century," the magazine which published King's letter.

The letter, smuggled out of his solitary confinement, began with feigned cordiality, "My dear fellow clergymen," but quickly addressed the "outsider" charge, noting he was invited by a local affiliate of his Southern Christian Leadership Conference., adding "I am in Birmingham because injustice is here." "You deplore the demonstrations that are presently taking place in Birmingham.

But I am sorry your statement did not express a similar concern for the conditions that brought the demonstrations into being...The white power structure of this city left the Negro with no alternative." "Birmingham is probably the most thoroughly segregated city in the United States.

Its ugly record of police brutality is known in every section of this country. Its unjust treatment of Negroes in the courts is a notorious reality. There have been more unsolved bombings of Negro homes and churches in Birmingham than any city in this nation."

One church bombing killed four black girls. He recalled that local Negro leaders had tried to negotiate. Merchants promised "to remove the humiliating racial signs from the stores," but changed nothing.

"We were the victims of a broken promise." Therefore, they trained for "direct action." Volunteers were asked, "Are you able to accept blows without retaliation?"

He charged, "Constructive nonviolent tension is necessary for growth...We know through painful experience that freedom is never voluntarily given by the oppressor; it must be demanded by the oppressed. "For years now I have heard the words "Wait." This "Wait" has almost always meant "Never."

It has been a tranquilizing thalidomide, relieving emotional stress for a moment, only to give birth to an ill-formed infant of frustration." He said he found himself "stammering to explain" to a six-year-old daughter why she can't go to a public amusement park, because "Funtown is closed to colored children."

He outlined why some laws had to be broken: "All segregation statutes are unjust because segregation distorts the soul and damages the personality. It gives the segregator a false sense of superiority, and the segregated a false sense of inferiority." King noted that "conniving methods are used to prevent Negroes" from voting.

"There are some counties without a single Negro" able to vote though they are "a majority of the population." He added that he was "so greatly disappointed with the white church and its leadership...I felt that white ministers, priests and rabbis of the South would be some of our strongest allies."

But they have been "more cautious than courageous and have remained silent behind the anesthetizing security of the stained glass windows."

Stung by his charge, thousands of white clergy joined the demonstrations. A year later the U.S. Civil Rights Act removed apartheid laws across the land.

Michael J. McManus, President of Marriage Savers and a syndicated columnist