Obama challenges Congress in $4tn budget gamble

Mr Obama hopes if talks fail, the Republicans will look like ideological hotheads

They are talking big at the White House.

Millions, billions, trillions, gazillions. The numbers are so huge as to be meaningless.

But forget any idea that this is about economics. It is politics in the raw.

President Barack Obama is playing double and quits. He has offered to double his package of cuts. From $2 trillion (£1.25 trillion) to $4 trillion.

His apparent offer to cut pensions (Social Security) and healthcare for the elderly (Medicare) will horrify many of his own supporters.

If the Republicans quit, refuse to do a deal in the face of what looks like the president being so willing to compromise that he is damaging his reputation with his own party, they will look like ideological hotheads.

Just to make sure they are put on the spot the president has laced his package with tax increases, which he knows are anathema to most Republicans.

He's already accused them of holding a gun to America's head in order to help the wealthy.

This may not work. The public may decide the Republicans are the ones being reasonable, that the president's proposed cuts are not big enough or even that the debt ceiling shouldn't be raised anyhow.

But the stakes are high. Mr Obama was elected in part on the big cuddly vision of bringing all sides together, to ending Washington politics as usual. That clearly hasn't happened.

So he has to have a story to explain why red and blue has not merged into a consensual purple. Indeed since he took office the gap between Republicans and Democrats has widened.

His latest offer of cuts is designed to make a specific argument - that he is willing to go the extra mile, to stick his neck out, but that his opponents are so entrenched in their narrow political foxhole that they would rather cause another economic crisis than make a single compromise.