WASHINGTON -- Call it government by lurching. Much of what Congress does now is temporary fixes. Lower student loan rates, but only for a year. Massive tax cuts that expire in December. Transportation funding, but only for two years. Not to mention a federal budget that probably won’t be completed the way it should, or the wrenching decision to raise the nation’s debt limit, likely to be repeated again early next year.

“Government by expiration dates,” in the words of Michael Franc, the vice president of government studies at the Heritage Foundation, a conservative Washington research group.

The quick fixes spawn turmoil among consumers and companies. They can’t plan far ahead, always unsure what the tax code will be or what the next federal contract might bring. And there appears to be no end in sight to the Band-Aids.

The temporary-fix Congress has many roots. Political parties, as well as the electorate itself, have become more polarized. Compromise is riskier.

“I do not recall any time in recent history in which gridlock was so prevalent on Capitol Hill – and for no reason other than simple electoral politics,” said Craig Holman, government affairs lobbyist at Public Citizen, a nonpartisan watchdog group.

The biggest roadblock? “It’s the money,” said Rep. John Mica, R-Fla., the chairman of the House Transportation and Infrastructure Committee. Budget deficits have soared, making it hard to approve spending without offsetting spending cuts or tax increases – a tough task.

Most Republicans refuse to consider any tax increases. Democrats routinely resist big reductions in popular social programs. With Democrats controlling the Senate and the White House, and Republicans holding a strong majority in the House of Representatives, inertia is common.

As a result, the last two years have seen a string of showdowns that ended with messy, temporary solutions.

Early 2011 saw a last-ditch deal to avoid a government shutdown. The battle last summer over the national debt featured intense White House-Republican talks and a last-minute deal that President Barack Obama signed just hours before the deadline for raising the debt ceiling.

In the fall, lawmakers agreed to extend the expiring Social Security payroll-tax cut for two months, and then, this February, for another 10.

Lawmakers see little value in giving in to reach any kind of lasting agreement, a departure from even the recent past. President Ronald Reagan, the hero of modern conservatives, said in his 1990 book, “An American Life,” “If you got seventy-five or eighty percent of what you were asking for, I say, you take it and fight for the rest later.”

Today, though, “compromise has become a dirty word,” said Ilisa Halpern Paul, managing government-relations director at the Drinker Biddle & Reath law and lobbying firm in Washington.

Until the last 20 years or so, parties tended to be less homogenous. Democrats could count on support for social and civil rights initiatives from New England Republicans. Republicans leaned on Southern conservative Democrats for help with social policy and fiscal belt-tightening measures.

Twenty years ago, the seven states from New York through New England sent a bipartisan blend to the House: 37 Democrats, 19 Republicans and one independent. Today, their ranks diminished because of smaller populations, the same region sends 41 Democrats and 10 Republicans.The House Democratic Blue Dog Coalition, a bloc of Democratic conservatives and moderates, has 25 members, fewer than half the 54 just two years ago.