Consider these quirky and out-of-character political developments. Our aggressively conservative president reverses positions and is ready to fight for passage of a $4.3 billion jobs program. This is followed by the House Democrats, who, prior to the 1982 elections, passed a more expensive jobs bill (which the president then threatened to veto) and whose liberal ranks were subsequently swelled by those election results, first criticizing the president's initiatives as inadequate, then calling for cooperation with the White House.

To understand these major role changes in American politics requires some brief exposure to political thinker William Schneider. As Schneider explains, there are two different types of political issues: "valence" issues and "position" issues. Valence issues are those on which candidates and voters are in substantial agreement on values and desirability. Most Americans obviously prize fairness, integrity, clean air and economic growth, just as most Americans oppose inflation, unemployment, violent crime, and governmental inefficiency. On valence issues, candidates compete not on the end to be achieved but instead on who would be more committed and capable in achieving that end.

"Position" issues are those on which there are real and opposite sides: ERA, abortion, the Panama Canal. They excite passions, enlist activists, and attract TV minicams. But according to Schneider and most pollsters, most of us pick our presidents on valence issues.

Generally parties and candidates win elections by emphasizing those valence issues on which they are perceived to be more effective than their opponents. Democrats have long been regarded as being more competent in dealing with unemployment than Republicans; Republicans have had a clear advantage on their perceived ability to handle inflation. But President Reagan, unwilling to leave the entire "unemployment and fairness" field to the opposition, risks raising those valence issues--through a federal jobs bill-- even higher in the public consciousness.

So why do the House Democrats forfeit their advantage on the jobs and unemployment issue? Have they become bipartisan converts overnight? Probably not. Congressional Democrats believe they will get most of the voter credit for any jobs package enacted and are unwilling to be seen as "confrontational" or "obstructionist"--two more valence issues.

Valence issues--economic growth, peace, fairness-- now dominate our politics. The anxiety and uncertainty so prevalent in our personal lives--one-third of last November's voters worry that a household member will be out of work this year--have invaded our politics. Political theology hasn't worked. That's one reason why the House Democrats are tentatively supporting the Reagan anti-recession package. As Bill Schneider would explain it, the valence issues right now are going the Democrats' way. But if the hard-lining president, with the firmly established perception of toughness, could achieve an arms control agreement with the Soviets, then peace--a most powerful valence issue, would redound to Ronald Reagan's advantage.