By seeking to drop the two most politically explosive charges against former National Security Council aide Oliver North, Independent Counsel Lawrence Walsh is simply bowing to the inevitable.

As long as the White House refused to compromise national security by letting secret documents be used in open court, there was little chance of convicting North on charges of conspiracy and theft of government property.If the court goes along with abandoning these charges, it should take the wind out of North's efforts to subpoena President Reagan and Vice President Bush to testify in the trial scheduled to begin Jan. 31.

The move also appears to eliminate any possibility for a full hearing in court on whether North, as he claimed, had the approval of his White House superiors when he created the secret scheme to sell arms to Iran and then divert some of the profits to the Contra rebels in Nicaragua.

But don't jump to the conclusion that justice is being thwarted.

The fact remains that the Iran-Contra scandal has been exhaustively and repeatedly investigated by the Tower Commission, by Congress, and by the Pentagon. The upshot of those investigations is that the White House's culpability clearly included ineptitude but stopped short of intentional wrong-doing. It's hard to believe the courts would have uncovered anything worse.

As for former Lt. Col. North, the proposed abandonment of the two charges still leaves him facing 12 other criminal charges that could, if he is convicted, result in a total of 60 years in prison and $3 million in fines.

Clearly, the rest of the case against North is still impressive. The remaining charges are felonies that should be easier to prove than the conspiracy and theft counts would have been and involve far fewer national security problems.

Among other charges, North remains accused of lying to Congress and presidential investigators and obstructing them, illegally destroying documents, embezzling $4,300 in traveler's checks and accepting a free $13,800 security system for his home. He has admitted to feeding hundreds of classified documents into a shredder as Justice Department investigators were looking into reports of the arms sales and diversion of funds.

Though many Americans look upon North as a hero and a patriot, he is a flawed hero at best. By destroying important documents, North in effect took the indefensible position that only a special elite - an elite that excludes key officials in both the executive and legislative branches of government - can be trusted with secrets.

However honorable North's intentions may have been, his judgment was faulty. So serious are the remaining charges against North that a presidential pardon still should be out of the question at least until after he has had his day in court.

Then, if North is convicted, the White House should think twice about the kind of precedent that would be set by letting patriotism be used to justify the destruction of important government documents.