US Debt Ceiling

Does Vince Cable know what he's talking about? I ask because (according to the BBC web site) in the Andrew Marr show, Vince Cable attacked leading US Republican politicians as "nutters" who were "holding up a deal to reduce US government debt".
However, everywhere that I have read about the "US debt crisis" I am told that the problem is that Obama wants to raise the debt ceiling to enable the country to borrow more.
Perhaps Saint Vincent would like to explain to me how increasing the amount that you borrow can reduce your debt.
Which is why I no longer bother to watch the Andrew Marr show as he is apparently unwilling to challenge such ludicrous contradictory statements.

And as for the BBC's line that the US will be unable to pay any employees or pensioners if an agreement is not reached perhaps they would like to explain why? Taxation revenue will continue to come in as usual, all it means is that the US government will not be able to increase its expenditure.

I just wish we had a similar arrangement in Britain, with a cap on government borrowing. Perhaps if we'd had such an arrangement when Brown was in financial control, we might not be in the mess we are today.