It now appears that Americans will have a new national holiday, named for the Rev. Dr. Martin Luther King Jr., the galvanizing civil rights leader of the 1960 s. The US Senate appears poised to pass a bill establishing the holiday; the House has already approved it; and President Reagan has said he will sign it. The holiday would be observed the third Monday in January, beginning in 1986.
The proposal explicitly honors the achievements of Dr. King. Beginning with his 1955 leadership of the Montgomery bus boycott, he made many Americans, black and white, aware that racism is morally corrosive - not only to black Americans, but also to those whites who practice it. He preached nonviolence, attracted many supporters, and won the Nobel Peace Prize. He was a key reason that in the mid-1960s Congress passed a series of laws aimed at providing equality of opportunity to black Americans.
Beyond Dr. King's own accomplishments, the proposal is an implicit acknowledgment of the past and present contributions of black Americans in general - from slave, farmer, and factory worker to educator, businessman, and government official. Sadly, for more than three centuries most black Americans labored in legal inequality in a nation whose Declaration of Independence promises: ''We hold these Truths to be self-evident, that all Men are created equal . . . .''
As usually happens in a democracy, politics plays a part in the apparent success this year of the 15-year effort to have Dr. King's birthday named a holiday. Both Republicans and Democrats are aware of the importance of the black electorate in next year's national elections; just before the House voted two months ago, some Democrats asked Republicans whose support they needed whether they wanted to be considered insensitive to minority aspirations.
A number of understandable concerns have been expressed by those who opposed adding this 10th national holiday. One is precedent: The nation obviously cannot establish national holidays for all the ethnic groups that have contributed to it. Where does the country stop?
But Dr. King and black Americans occupy a special place in the history of the nation. Their contributions - past, present, and future - need to be appreciated by all.