Republicans spent October feeling as the Light Brigade must have felt. Cannon to the right of them, cannon to the left of them, cannon in front of them volley'd and thunder'd. But when the smoke cleared, the Republican brigade, though diminished, was not decimated.

As is inevitable when 468 seats in the national legislature are at issue, the electorate has made a loud noise. But, then, so did the Hindenburg when it exploded. Did Tuesday's noise, unlike the Hindenburg's, communicate a thought? If so, it is this: the Republican Party deserves a reprimand, but the Democratic Party does not deserve a mandate.

Rarely has a party in opposition managed to make so little of so much in the way of nasty economic numbers. The 10.1 percent unemployment figure is just the beginning. In the first full year after Reagan's tax cut became law, the unemployment rate increased by one-third. It increased twice that fast among factory workers. One in five persons in the construction industry was unemployed.

An ABC-Washington Post poll of registered voters showed that 20 percent of the households contained at least one person who had lost a job in the last year; 16 percent of those households had at least one person who had taken a lower-paying job; 19 percent had at least one person whose hours had been shortened. So the "income-reduced" group is considerably larger than 10.1 percent of the work force. In the 1975 recession, nearly 60 percent of the unemployed received benefits under federal programs. Today, only 41 percent are receiving benefits.

In the first quarter of this year, the federal deficit, on an annualized basis, was $126.4 billion, more than the entire amount of private savings $115.4 billion). In September, the Commerce Department reported that industrial investment -- the primary goal of supply-side economics -- will decline 4.4 percent this year. That is not surprising, considering that in the first half of this year, corporate profits plunged to $140 billion (at an annual rate), from $183 billion in 1980.

Democrats, contemplating the disproportion between the large opportunity and small yield, must be in a mood to break the Sixth Commandment. But whom should they murder? Nobody. Instead, they should take a fresh look at a familiar measurement -- the "misery index" -- and at an intellectual development not confined to this nation.

Seymour Martin Lipset, a sociologist, notes the difference of durability of governments in two recent four-year periods, 1975-78 and 1979-82. From 1975 through 1978, the average annual rate of GNP growth in 25 developed countries was 3.2 percent, but just 0.84 percent from 1979 through 1981. In the first period, just six governments changed hands in the 17 democracies where there is regular alternation between two major parties or coalitions. In the next period there have have been 13 changes. The variation, Lipset suggests, is explained by the misery index --the sum of the inflation and unemployment rates. In the United States, the misery index in 1980 was 18.9. In 1982, through September (and including the 10.1 percent unemployment) it has dropped to 14.9. One reason Republicans did not do worse is that by one measure conditions are better.

Robert Samuelson of the National Journal notes "a broad retreat -- throughout the industrial world -- from a 'full employment' economy. The major change is intellectual. Governments no longer embrace aggressively expansionary policies, because they no longer think they work" -- work without intolerable inflation. In the first quarter of 1982, unemployment in Germany was 5.5 percent, up from 0.9 percent in 1973. In the same period, unemployment in Britain went from 3.2 percent to 12.4 percent; in Italy from 6.2 percent to 9.2 percent; in France from 2.5 percent to 8.2 percent.

Even the most formidable persons have weaknesses. Achilles had his heel. Othello was prone to jealousy. Many Democrats tell people the one thing everyone knows is false: that the choices confronting government are easy for the morally upright.

The closest thing to a Democratic program is the House Democratic Caucus's call for 25 new or expanded federal programs, three new or expanded capital allocation programs, two new tax increases and 12 new tax decreases. The caucus says the "cornerstone of the Democratic vision" --cornerstones with vision, yet--is "growth and fairness." But surely contemporary politics must face the fact that attempts to legislate social fairness can interfere with growth, and slow growth is a regressive phenomenon: the affluent get more affluent more slowly, but most of the poor remain poor.

The election results constitute a collective shrug, a middle-aged nation's expression of ambivalence and resignation. Americans are too uncomfortable to be content, but they are too unillusioned to be disillusioned.