Why did Republicans go to the trouble and expense of winning the midterm elections? It looks like they're about to prove, once again, that you can get your way in Washington without a congressional majority - if you have a firm sense of purpose. Maybe the Democratic Party will find one someday.

Or maybe not. Sigh.

What has me exercised - okay, frothing - is the ongoing fight over the Bush tax cuts for the wealthy, which are set to expire at the end of the year. By all rights, this shouldn't be a fight at all. The Republican position is so ludicrous that it beggars belief.

Here's what they argue: Extend the tax cuts for the richest Americans - in fact, make them permanent. Doing so would increase the deficit by $700 billion over the next decade, but this doesn't matter. We did tell you that we're the party of fiscal responsibility, however, so to prove it we'll block the extension of unemployment benefits for millions of jobless workers. Three weeks before Christmas.

In other words, there's no additional money in the national coffers for the victims of the most devastating recession since the Great Depression. But to help investment bankers start the new year right, perhaps with a new Mercedes or a bit of sun in the Caribbean? Step right up, and we'll write you a check.

And there's more: Republicans contend that whatever the long-term impact of extending those tax cuts, it would be a mistake to let anyone's taxes rise when the economy is still struggling to find its legs. Some economists agree. But it's hard to find any economist who believes that ending jobless benefits is a good idea, since this money gets spent almost immediately - recipients, after all, are without other income but still have to pay for housing, food, clothing, transportation and other necessities. That's why unemployment payments pack such a stimulative punch. Tax savings for the rich, by contrast, have a much weaker economy-wide impact; the well-to-do, whose basic needs are already met, may decide to skip the new car or the vacation and just put the money in the bank.

So why is there even an argument? Certainly not because of any statement "the American people" might have made in last month's election. Every poll I've seen indicates that the Democrats still have public opinion on their side. They also hold the presidency and big majorities in Congress - and even in January they'll still control the White House and the Senate. Yet not only is there an argument over the tax cuts, but Republicans are also seen as having the upper hand.

That's because the GOP has been disciplined and purposeful in pursuit of its goals. I happen to think those goals are cynical, situational and ultimately bad for the country: Block the Democrats whenever and wherever possible, try to limit President Obama to a single term, and prevent any meaningful departure from the trickle-down economic philosophy that has left the nation's finances in such a parlous state. It's an agenda that may lack nobility, but not clarity.

What is the Democratic Party's bottom line? Who knows?

The White House, for the umpteenth time, has approached a negotiation by signaling in advance its willingness, if pushed to the wall, to make major concessions - in this case, a temporary tax-cut extension for the rich. It doesn't take a genius to recognize this as a flawed bargaining strategy. Voters may want more bipartisan cooperation in Washington, but I believe they also want their president to fight for the principles that got him elected.

Democrats in Congress are all over the map. Speaker Nancy Pelosi and the House leadership, predictably, are ready to have a fight on what they see as favorable political terrain. In the Senate, Democrats have to parse the implications of a GOP threat to halt all business until the tax cut issue is dealt with. And everyone wonders whether the White House intends to stand tough, or has decided to give in, or has already caved - or, perhaps, has a specific preferred outcome in mind. If so, the White House doesn't seem to have made clear what the objective is, much less how to get there.

Power without purpose, in fact, doesn't get you anywhere.

eugenerobinson@washpost.com