When Washington planning officials presented their blue-covered regional transportation plan to President Eisenhower at the White House in 1959, they started a series of arguments that has continued for 18 years and still shows no signs of abating.

The first and fiercest argument was over whether to build a rail rapid transit system to supplement an extensive proposed network of freeways. It was settled in two ways: With a decision to proceed with the subway, and with a sharp curtailment of the highway plans.

Arguments over the extent and the shape of the rail system - now called Metro - remain a live issue today.

Policy decisions made by regional and federal politicians in past years have limited the options available to those who must decide where Metro goes from here. The final version of Metro, with perhaps no more than 60 of the projected 100 miles, may satisfy nobody in terms of costs, route structure and community impact.

When the transit program began under a federal agency that won a construction authorization from Congress in 1965, it was to be a bare 25 miles, not extending far outward from Washington's downtown core. A single short line was to reach across the Potomac to the Pentagon.

Walter J. McCarter, an experienced and conservative transit executive from Chicago, who was directing the program at the time, talked of building lines just long enough to "break the congestion barrier." Passengers would reach the railheads by bus or automobile.

If those projected short rail lines proved successful, it was expected that they would be extended later. Construction money would be raised as needed.

That is the way it worked in Toronto, which has one of the continent's best-coordinated and effective transit systems. Two relatively short rail lines shuttle passengers in and out of downtown.

But in Washington there was widespread community zeal, fueled by growing resistance to the freeways, to build something more ambitious.

Area politicians took the cue. Despite contrary advice from the subway's strongest congressional backer, Rep. Basil L. Whitener (D-N.C.), they created the Washington Metropolitan Area Transit Authority with a board representing the area's local governments but lacking direct federal participation.

An early decision was reached to build the full regional system under one all-inclusive financial plan, designed to pay the entire cost. The inflation of the Vietnam war era, among other things, made that impossible, and has led to the proposals for cutbacks.

In their initial zeal to push the routes as deep as possible into the suburbs - to get "the biggest bang for the buck" - the Metro adopted a track layout that may make sense if built to a full 100 miles. It is flawed if those same routes are truncated or eliminated outright.

The travel corridor directly north of downtown Washington is a case in point.

Metro's adopted plans call for two routes, one going out the B&O Railroad right of way through Silver Spring to the Wheaton-Glenmont area, the other going out 14th Street and perhaps Kansas Avenue to and beyond College Park.

If the 14th Street route is dropped - and it is vulnerable - the remaining line along the B&O tracks is badly off center from the corridor's population. And a truncation of the line at or near Silver Spring could attract a large volume of unwanted bus and automobile traffic to that already congested area.

A similar problem of truncation exists in Northern Virginia, where the Vienna route (which crosses North Arlington) could be cut short at the Ballston station at Fairfax Drive and North Glebe Road. The impact of traffic by commuters seeking to reach the train station and park near it could be devastating to a neighborhood unprepared for the deluge.

Operationally, such truncation would be troublesome, since the only train storage yard and maintenance shop on the line would be eliminated. Empty trains would have to be shuttled all the way from New Carrollton, in Prince George's County, to Arlington.

Another aspect of truncation could be embarrassing to Metro and local officials. A subway has already been built beneath 7th Street in downtown Washington, from M Street SW to H Street NW, connected by a new bridge at 14th Street to the Pentagon station in Virginia.

Running this fragment of a line would make little sense, and could become a multimillion-dollar monument to bad planning, unless a decision were made to extend the line as now projected up 14th Street, or over to Anacostia and into southern Prince George's County.

On the other hand, the existing routes in and near downtown Washington, including the 12-mile route that begins operating next Friday, provide a superb distribution network in the manner contemplated by McCarter back in 1968.

Metro's planning problems are inter-twined with its financial problems in a way that one cannot be considered apart from the other.

When it adopted a route layout, the Metro board also adopted an official financial plan, a program that was intended to pay for completing the entire subway system as a single package for a set price.

Originally that price was $2.5 billion. Soon after groundbreaking in 1969, it rose to $3 billion. Various factors, notably the inflation of the Vietnam war period, have pushed it to around $5 billion.

Metro, effectively having run out of the funds earmarked by its financial plan, is now being financed from funds transferred from abandoned interstate highway projects.

Operating losses were not predicted by Metro officials when the rail system was planned and when the area's bus companies were acquired.

One cause of Metro's financial problems was an early decision by officials to build the system with the smallest possible contribution from area taxpayers. Of the $3 billion cost expected in the early 1970s, only $723 million was to be raised locally.

Indeed, Metro and federal officials invited much of the community's cynicism over the rising costs of Metro by testifying in 1972 that the expected efficiencies of public bus ownership here would avert the deficits suffered by every other city.

Costly as it may be, Metro could turn out to be a major asset in the years ahead. If petroleum-based energy sources dry up, it could insure the capital region's future mobility to a much greater degree than those planners who handed the report to Eisenhower might have dreamed.