IF YOU are worried about how much you owe on your credit cards, this might put things in perspective: America’s national debt limit was increased yesterday to $9 trillion. That’s $9,000,000,000,000 — enough to buy Buckingham Palace 9,000 times.

The increase, passed by Congress, allows the Government to borrow another $781 billion (£447 billion), increasing the national debt limit — the maximum America can borrow — from $8 trillion and $184 billion to $8 trillion and $961 billion.

If the debt ceiling, which is set by Congress, had not been raised by March 24, the Administration would not have been able to borrow more money and the US would have begun to default on its domestic and foreign obligations, an untenable consequence.

The vote to increase the debt limit, requested by the White House, is the fourth since Mr Bush took office. In 2001 the national debt was $5.7 trillion. Today it has ballooned to $8.2 trillion, figures rarely talked about in Washington.

The national debt is the total amount owed by the Government. It is not to be confused with the federal budget deficit, which is the yearly amount by which spending exceeds revenue. When budget deficits are big, the national debt inevitably increases.

When Mr Bush took office he inherited a $236 billion budget surplus. Bill Clinton, his predecessor, had used budget surpluses to pay down some of the national debt in his last two years in office. Mr Bush also inherited some extraordinarily overoptimistic projections. Experts pronounced that budget surpluses would increase to $5.6 trillion over ten years, and there was even heady talk of paying off the entire national debt with the proceeds.

Since then a combination of factors — the September 11, 2001, attacks, unexpectedly low tax revenues, Mr Bush’s tax cuts and runaway government spending — have plunged the yearly budget back into deficit. This year it will reach nearly $400 billion.

What worries many analysts is the amount of US debt financed by foreign governments and banks, particularly in Asia. The national debt is split between publicly held debt — money owed to US and foreign investors — and money owed to branches of the Government. Nearly half the publicly owed debt is held by foreigners. Japan is the biggest creditor, at $668 billion. China, the second-biggest, recently increased its stake by $40 billion to $263 billion.

“We used to have much less held by foreigners,” Alice Rivlin, a former budget director for Mr Clinton, said. “It makes you much more vulnerable to people’s agendas.”

Historically, today’s national debt is the highest in dollar terms, but not as a percentage of GDP. In 1946 it was $270 billion — 122 per cent of GDP.

Today it is 65 per cent of GDP, very close to the postwar high of 67 per cent in 1996.

America has had a national debt since 1791, when it was $75 million. Today it rises by that amount every hour.

$9 TRILLION

Would build 28 Eiffel Towers — constructed out of gold.

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