BY CONNIE CASS

Associated Press

WASHINGTON

--Efforts to save the nation from going over a year-end "fiscal cliff" were still in disarray as lawmakers returned to the Capitol to confront the tax-and-spend crisis. A tone-setting quotation was Democratic Sen. Harry Reid's assertion that the House under Republican Speaker John Boehner had been "operating with a dictatorship."

President Barack Obama flew back to Washington from Hawaii after telephoning congressional leaders from his Christmas vacation perch. Once back, he set up a meeting with leaders of both parties at the White House late Friday to make a fresh attempt to find a solution before tonight's deadline.

A look at why it's so hard for Republicans and Democrats to compromise and what happens if they fail to meet their deadline:

NEW YEAR'S HEADACHE

Partly by fate, partly by design, some scary fiscal forces come together at the start of 2013 unless Congress and Obama act to stop them. They include:

Some $536 billion in tax increases, touching nearly all Americans, because various federal tax cuts and breaks expire at year's end.

About $110 billion in spending cuts divided equally between the military and most other federal departments. That's about 8 percent of their annual budgets, 9 percent for the Pentagon.

Hitting the national economy with a double whammy of tax increases and spending cuts is what's called going over the "fiscal cliff." If allowed to unfold over 2013, it could lead to recession, a big jump in unemployment and financial market turmoil, economists predict.

IF THEY MISS DEADLINE?

If New Year's Day arrives without a deal, the nation shouldn't plunge onto the shoals of recession immediately. There still might be time to engineer a soft landing.

So long as lawmakers and the president appear to be working toward agreement, the tax hikes and spending cuts could mostly be held at bay for a few weeks. Then they could be repealed retroactively.

The big wild card is the stock market and the nation's financial confidence: Would traders start to panic if Washington appeared unable to reach accord? Would worried consumers and businesses sharply reduce their spending? In what could be a preview, stock prices in the U.S. and Europe dropped Friday on waning hopes that Obama and key lawmakers would reach an 11th-hour compromise.

IF THEY NEVER AGREE?