KANDAHAR, Afghanistan - A year ago, mobile phones worked just fine in the pomegranate orchards and vineyards along the Arghandab river on the outskirts of Afghanistan's second largest city, Kandahar.

That was before the Taliban took over the west side of the river and blew up the telephone relay tower, cutting off the entire valley north of Kandahar from communication with the outside world.

Militants have been making startling gains in the area around Afghanistan's second largest city, which is the birthplace of both the Taliban movement and President Hamid Karzai.

To turn back the tide, the area is likely to receive the largest share of the tens of thousands of reinforcements President Barack Obama will announce this week after a request from his commander, General Stanley McChrystal.

In his August assessment of the war, McChrystal described the city as the key geographic objective of the Quetta Shura Taliban, the main faction led by Mullah Omar, the reclusive Taliban leader driven from power in 2001.

U.S. forces who arrived this year now patrol mainly the east side of the Arghandab. The west side belongs to the militants.

Schools on the west bank have shut after several were blown up and attacked. Even on the east bank some schools have closed after receiving threats. A Canadian-built clinic never opened -- the doctor was killed and the building booby-trapped with bombs.

McChrystal's new counter-insurgency strategy calls for a focus on population centres, and there is no bigger population center under more serious threat than Kandahar.

CANADIAN CASUALTIES

For years Kandahar was the responsibility of a Canadian NATO contingent, which suffered 133 deaths, the third heaviest casualties of the war behind only the United States and Britain.

The Canadians, never more than a few thousand strong, lacked the manpower for a full-blown counterinsurgency campaign. They have since announced they are leaving by the end of 2011 and are turning over the province to U.S. troops.

Under plans in place before McChrystal took command, Washington sent a new brigade of ground troops to Kandahar this year, but they accounted for only about 10 percent of the 36,000 reinforcements that have arrived since Obama took office.

Most of this year's combat reinforcements were instead sent to neighboring Helmand province, Afghanistan's main opium growing region, where nearly 10,000 extra U.S. Marines doubled the strength of a British force.

U.S. commanders defend that decision as necessary to cut off Taliban infiltration routes and drugs income, but they acknowledge it left Kandahar under-manned.

With so few troops on the ground, Washington and Ottawa have relied instead on Afghan power brokers to keep the peace. A complex local tribal structure keeps authority in the hands of landlords and chiefs, many with dubious backgrounds.

The most powerful public official is provincial council chief Ahmad Wali Karzai, the president's half brother, who denies persistent Western media reports that he is involved in the drugs trade and also on the payroll of the CIA.

If Western commanders are hoping to protect the population of Kandahar with more troops, they have yet to convince local people, who view the prospect of reinforcements with dread.

We will not benefit from the U.S. government increasing its troops, said Agha Lala, a Kandahar money changer. It will result in more suicide attacks and roadside bombs and more loss of civilian lives.

Shopkeeper Shah Mahmood said foreign troops had so far brought only misery, violence and bloodshed.

The foreigners bombed our homes, our villages and killed thousands of civilians, forcing many people to seek revenge.

(Additional reporting by Jonathon Burch; Writing by Peter Graff; Editing by David Fox)

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