(Adds deaths of two ISAF soldiers)
By Jon Hemming
KABUL, June 3 (Reuters) - U.S. General David McKiernan took command of around 50,000 troops in NATO’s International Security Assistance Force (ISAF) in Afghanistan on Tuesday, pledging that anyone who stood in the way of security would be dealt with.
McKiernan takes over ISAF at a time when the international community is trying to put new momentum into military and aid efforts in Afghanistan, but the Taliban show few signs of bringing an end to their insurgency.
ISAF has grown from some 36,000 troops a year ago and the Afghan army has more than doubled in size from just over 20,000 at the beginning of last year to about 57,000 now.
The large Taliban offensives in 2006 in the south, in which the insurgents suffered heavy losses, have not been repeated and many militant commanders have been killed or captured in a campaign to decapitate the hardline Islamist guerrilla movement.
But the Taliban have answered back with suicide bomb campaigns across the country that have undermined the perception of security among Afghans frustrated with the seeming inability of their government and Western troops to stop the attacks.
"While today marks a transition in commanders, the mission must continue without missing a beat," said McKiernan after taking command from retiring U.S. General Dan McNeill.
McKiernan described ISAF’s mission as: "Support to the government of Afghanistan in bringing security, reconstruction and development, and effective governance to the country."
"Insurgents, foreign fighters, criminals and others who stand in the way of that mission will be dealt with."
Afghan President Hamid Karzai said McKiernan faced a difficult task.
"We will have a lot of days of working together, a lot of happy days, but also some sad days. We will lose lives, NATO soldiers will lose lives, Afghan soldiers, Afghan personnel will lose lives ... but we must remain steadfast," Karzai said in a speech at the handover ceremony.
Underlining the danger and the difficulty, two ISAF soldiers were killed and another wounded in eastern Afghanistan, the force said on Tuesday. ISAF does not release the nationalities of those killed, but most of troops in the east are American.
Karzai, facing elections next year, has been increasingly critical of the international presence in Afghanistan, saying foreign forces are heavy-handed and the aid effort lacks coordination and effectiveness.
Many in ISAF and the United Nations meanwhile now often talk of the need for good governance in Afghanistan, one of the poorest, most corrupt countries in the world and its biggest producer and exporter of opium and heroin.
Afghanistan is due to meet its international donors in Paris on June 12 where Karzai is to ask for $50 billion to fund a development plan his government has drawn up.
While it is far from clear whether anything like that figure will be raised, the international community is likely to demand in return for its continued backing a new commitment from Karzai to fight official corruption. (Editing by Jerry Norton)