IF THE CHOICE is between Jimmy Carter and Ronald Reagan, and it is, then the Democratic candidate should be elected.It is testimony to both the unrelieved awfulness of Mr. Carter's campaign and the (at least, comparatively) straightforward effort of Gov. Reagan, that for people like ourselves there should even have been any conflict or hesitation at all. For much as we prize and insist upon our intellectual and political independence around here, no one who has read this paper over the years would have exactly figured Ronald Reagan for The Washington Post's dream candidate. One of the ironies of campaign '80 has been the way in which Jimmy Carter's obsessive drive to discredit and destroy the Republican candidate as anyone a normal, unbloodlusting person could even consider voting for has done so much to harm Mr. Carter instead. But more on that in a moment.

Mr. Reagan's achievement over the past year has been notable. He has not just managed to dispatch a formidable array of Republican competition. He has also sought with some self-evident degree of success to enlarge his constituency, his understanding of other people's points of view and (thereby) his fitness for the office. Some people argue -- soundly, in our view -- that the virtue of the American two-party system is that it entices extremes toward the center and compels within each party a coalition of broadly compatible political forces, rather than creating a separate splinter party for each. But many of these same people invariably get very out of sorts when someone like Gov. Reagan actually campaigns on precisely this principle. We do not belong to the all-change-is-flip-flop school ourselves. We think that this aspect of the progression of Gov. Reagan's campaign has been admirable and responsible. We just aren't where he has ended up on some of the big, crucial questions -- on a couple of them, including his approach to certain civil rights and personal freedom matters, not even close.

Another way of saying it is this: there is a tremendous burden of proof on anyone who is seeking to unseat an incumbent president from a position such as that Gov. Reagan began with: a man who has had no experience in national government and who is a relatively late arrival in mainstream politics. We think Mr. Reagan has done much to overcome that burden, but, for us, not enough. We reject flatly the Carter administration's charge that the man and his entourage represent positions too extreme and bizarre even to be taken seriously compared with its own positions on, for example, managing the economy and influencing foreign affairs. But for us, to meet this burden of proof, Mr. Reagan would have had to set forth economic and foreign policy alternatives much more self-evidently likely to improve the degraded American condition at home and abroad than the ones he has espoused. And on one fundamental issue -- the whole energy/conservation/environmental-protection complex of concerns -- we find ourselves generally and irredeemably at odds with Mr. Reagan's perception.

Four years ago in this space, after making what we called a "modest and rather tentative case for Mr. Carter's credentials" as a suitable replacement for Gerald Ford, we concluded: "If this doesn't strike you as much of an endorsement, well, that's fine: it isn't meant to be." Churlish to the last, we note today that the president, who has accomplished some things, appointed some good people, and made a few things work better, must take responsibility as much as he takes credit for the way the country and its interests look in 1980. The Carter administration can rightly boast some large-scale achievements -- in energy policy, for example, and in the enactment of some important, far-reaching reforms. But there is an enormous amount to do to strengthen the country's economic stability and to rescue its sagging security -- the latter being about much more than merely the amounts spent on this or that weapons system.

In both these realms the act of restoration will require of a president not just policies that look more or less okay on paper but also -- and perhaps critically -- a toughness and steadiness and maturity of feeling that are precisely what Mr. Carter lacked in this campaign. The so-called "meanness" issue was never trivial, because it was not about bad manners at a balloon-popping birthday party for the kids. It was about a president's revealing certain values in the manner of his combat for reelection; and people, we think, perceived in Mr. Carter's unfortunate show, not toughness (tough is the opposite of mean), but intimations of something ruthless, unsure and weak.

A just God will hear the prayers of all those who wish this campaign soon to be over. Maybe when it is, and if he wins, Jimmy Carter will find a moment to look within himself just a little critically and try to fathom what it was that he revealed that the rest of us found so disturbing and, to use his preferred epithet about someone else, dangerous. A man of such eminent and obvious self-discipline as Jimmy Carter could do worse than to apply that discipline to a little self-searching. But barring some unexpected and, we assume, unthinkable squalor in the attempts being made to get the hostages home, it seems to us that people like ourselves know enough now to know that the Democratic administration more nearly than its challenger embodies our ideas of what needs to be done. That is our decision. We may not be enthusiastic about it. But we are emphatic.