Sometime between now and July 4, the Supreme Court may hand down the most important decision on racial discrimination in a generation because it could determine whether the diversity movement has legal authority.

The suspense is much less a matter of which way the court rules on the legality of how students are assigned to schools in Seattle and Louisville, than how the decision is written.

Even supporters of the school-assignment plans that aim for certain racial balances in the student populations in those cities’ schools and their allies worry that the court’s new conservative majority will say their plans are unconstitutional.

The suspense – and the thing to focus on when the decision is handed down before the court adjourns for the summer – is how broadly it is written.

Simply put, the question is whether the court will decide to throw out these and other similar racial-balancing plans or – and this is where the decision could be so momentous – get into the basic question of whether diversity is a compelling government interest.

The school assignment plans in question are based on the idea that government can use its power to foster diversity.

When the civil rights movement began a half-century ago, government-ordered plans regarding programs such as school busing or affirmative action were based on the premise that they were needed to overcome the effects of specific racial discrimination.

In other words, a school district or a local government was required to bus children or hire more black firefighters because those communities had been guilty of discriminatory acts that in the past had infringed on the rights and prospects for blacks.

But over the years, as specific cases of discrimination have been dealt with, there has arisen the notion in both government programs and the private sector that racial diversity is important for American society.

The desire for diversity is the reason school officials in Louisville and Seattle came up with their plans, which in some cases put students of one race or another in a school they did not want to attend.

The parents of white students, who believed that their children were being discriminated against because blacks and other minorities were given preference for assignment to desirable schools, asked the courts to throw out the plans.

Virtually all the news accounts of the Supreme Court hearing on the case last fall speculated that the tone of the questioning by the justices indicated it would be surprising if the plans were upheld.

The unknown, of course, is whether the justices will take on the legality of the rationale that diversity is a compelling government interest. If they do, and should find that it is not, then this decision has the potential to reshape vast areas of American life – and not just involving government programs. If diversity is not a compelling government interest, then many programs involving race are in danger.

The need for diversity has become the mantra of private industry and higher education these days without the legal infrastructure provided by congressional act or Supreme Court dictate. It has evolved out of well-intentioned efforts to rectify the effects of racial discrimination.

Obviously there is no mention of diversity in the Constitution. Of course that does not mean that the court will find the concept unconstitutional. The right to an abortion is not anywhere in the Constitution, but the court in 1973 found that it existed as part of an existing right to privacy.

It is not hard to imagine the court finding diversity to be a compelling government interest – the standard for allowing the treatment of people of different races differently – to avoid upsetting the societal apple cart.

However, this is a court with two recently appointed justices – John Roberts and Samuel Alito – who are believed to have given the conservatives the majority they have long craved.

The angst on the left about their confirmation centered on the fear they would ban abortion.

Yet, it may well be that race, not abortion, will be the subject on which the Roberts court will make its first major mark on American life.

They key won’t be so much what they rule, but how they get there.