The Iraq 'surge' general will have to deal with the growing Islamic militant threat in a poorer and nuclear Pakistan. Yet that is only a part of his responsibility for Middle East and central Asia. The political situation in Pakistan worsens daily.
Pakistan is also stone cold broke. Pakistan needs about $15-billion to stay afloat.
Petraeus is uniquely qualified to fulfill his new role, but he will need a lot of help.
Petraeus takes charge of US Central Command
Mark Tran and agencies
guardian.co.uk, Friday October 31 2008 11.13 GMT
David Petraeus, the general who directed the Iraq "surge", today takes charge of US Central Command, where he will head American military operations in the Middle East and central Asia.
Petraeus has signalled his priority will be Pakistan, the first country he will visit after today's swearing-in ceremony in Tampa Bay, Florida.
Nuclear-armed Pakistan faces a growing Islamist threat, has had to ask for financial help from the International Monetary Fund, and faces impatient calls from the US to crack down on Taliban and al-Qaida militants operating from Pakistan into Afghanistan.
Petraeus, an expert on counter-insurgency, comes into his new job credited with pulling Iraq back from the brink of disintegration. During the surge, sectarian violence fell off dramatically and the US military speaks glowingly of a newly confident Iraqi army.
The general has been cautious about Iraq's prospects, insisting that the job is far from finished. He has said the war in Afghanistan is likely to prove even longer and harder.
Pakistan is shaping up to be just as difficult. Admiral Mike Mullen, the chairman of the joint chiefs of staff, has warned that any future terror attack on the US would come from Pakistan's western tribal regions, where the central government has little or no control. For US strategists, Pakistan may be considered a bigger immediate threat than either Iraq or Afghanistan.
"Dealing with Pakistan, where America's mortal foe al-Qaida is nestled alongside the Taliban, is clearly the most pressing problem we face," Bing West, a retired marine and former assistant secretary of defence, wrote in National Interest, the journal of international affairs and diplomacy.
Petraeus has acknowledged Pakistan will probably be altogether different from Iraq, where his counter-insurgency tactics succeeded. "Pakistan is going to do this on their own," he told rightwing thinktank the Heritage Foundation this month. "They have a very keen sense of sovereignty."
In an interview in Washington this week, a senior Pakistani official said his government was drawing up a more comprehensive strategy for fighting the insurgency, now regarded as the gravest threat to the government.
It would be carried out in cooperation with the US, but not on a US timetable, the official said. "We are going to run this."
There is tension between the US and Pakistan over the insurgency in tribal areas. The Bush administration has stepped up sending drone aircraft to attack targets in remote border areas inside Pakistan. Resulting civilian casualties have caused uproar among Pakistanis.
Petraeus's arrival at Central Command was not the original plan. The US secretary of defence, Robert Gates, wanted to move Petraeus from Iraq to the less demanding job of commanding US and Nato forces in Europe.
But Admiral William Fallon unexpectedly announced his retirement in February after a year at Central Command and Petraeus was named as his replacement.