The document in front of me -- 71 pages long, age-worn, bearing a warning that it is not to be published before 6 p.m. on Feb. 27, 1965--is called "Aggression From the North." I went looking for it and, uncharacteristically, found it, in one of my files recently. This is not the final, printed version of the paper, but rather a rough, mimeographed copy handed out to reporters at a State Department briefing that winter morning almost 20 years ago, a session that I attended. William Bundy, the assistant secretary for Far Eastern affairs, stood before us in an auditorium and presented the government's case--based on captured documents, weapons and so forth--that the war in South Vietnam was not a local insurgency; rather, he said, it was a Hanoi-supplied and -directed assault.

Waves of journalistic skepticism undulated through the room. Querulous, disbelieving questions were put. Earnest, I-swear-to-God answers came back. News clips from the period feature a photo of Secretary of Defense Robert McNamara displaying a captured Viet Cong rifle to a delegation from Congress. Does any of this remind you of anything?

What interests me especially about both that bygone presentation and the current, analogous ones concerning the warfare in Central America is the American government's misplaced confidence in the power of its documentary findings. Other governments, I note, publish their factual white papers after a foreign-policy disaster. We publish ours before. They are intended to persuade the unpersuadable--the beyond-reach domestic opponents and the completely intractable skeptics.

"Aggression From the North" has a lot to say about political direction, about the origins and supply routes of weapons, about the training sites of military personnel--in short, many of the same things we are hearing about in Central America today. But to me, the most revealing word it uses--and the word appears again and again, just as it does today--is this one: "evidence." Our government constructs a kind of legal brief for its foreign-policy actions on the assumption that dispassionate, right- minded jurors (that's us) cannot fail to be swayed. The lengths to which it will go can be amazing. Can you think of another nation where (as was reported here last week) the so-called secret intelligence agency would offer to fly legislators to the scene of its so-called secret war to see for themselves the merit and restraint of the operation?

"Fact-finding" is a governmental passion. From found facts all else is stubbornly expected to flow; I say "stubbornly" because the desired result almost never materializes. For the first thing that happens (this was true of "Aggression From the North," as it has been of most similar white papers ever since) is that a journalist or a congressman will assert that some of the evidence is either overstated or untrue. The errors cited may have been a result of haste or zeal, as distinct from a clear intent to mislead, or they may not be errors at all. But that doesn't usually matter: right or wrong, the whole paper will be seen to have been discredited. By the time its major premise has been vindicated, or at least shown not to have been completely crooked or mad (and this happens too), only history will be interested anymore. Those surviving doubters and others who actively resisted the "evidence" of the other side's various depredations will observe only, if they trouble to observe at all, that the other side may well have done these things, but probably wouldn't have felt the need to if we had not driven them to it.

The point is that all this case-making and courtroom argument and laying out of certain facts is a mugs game, a no-win proposition. This is because a lack of "evidence" is usually not the problem. What is preventing the acceptance of government's argument by those it seeks to convince is a disposition not to accept it. You can't really argue that out of existence. And even if some part of the factual presentation is accepted, the policy implications government sees in it will not be. "Yes"-- the rejoinder will come to an assertion of Soviet or Cuban or North Vietnamese involvement in the civil strife in some country where we seek to help the government--"Yes, they are certainly mucking about there. But who cares?" Or: "Do we want to start World War III over that?" Or: "Aren't they a bunch of crooks and despots themselves?"

The rejoinder, in other words, will be that any engagement with the defending government is either too dangerous in terms of a potential for military escalation or morally unjustifiable as the government is not worthy of our help. The alternative--letting nature take its course--is preferred, and it is this instinct not to engage in certain places that government keeps trying unsuccessfully to overwhelm with its presentations of yet more "evidence." The people in office seem unable to accept that they are contending with something other than a want of information in their critics. They are contending with a sentiment against engagement of the kind being promoted. It is this which they must overwhelm if they really hope to convert their opposition.

I don't think they can do it--not now, not in the current political atmosphere. I would divide the hard-core opposition roughly into those who are honestly and openly opposed to thwarting left-revolutionary movements or Soviet intervention wherever they occur around the world and those who always assert that there certainly are places where they would favor American action, although they never can seem to think of one this side of San Diego. But besides this kind of resistance, there is the resistance of many, many other Americans who have just become too skeptical of government's ways and too unconvinced of the importance of the dangers government cites and too ambivalent about what, if anything, we owe our various friends, allies and acquaintances in the world to rally to government's call.

These last are the people that government must move if it is to create any kind of consensus on foreign policy in Central America and elsewhere. What it must do is to present a cogent and persuasive rationale--moral, practical, political--for its desired course of action. People will not be moved by its facts, not even real ones.