KANDAHAR, Afghanistan — The most powerful man in Kandahar is alone in his reception room with two mobile phones and a string of prayer beads pinched between his finger and thumb.

He rises to greet his visitors, shakes hands, and sits again with a slight sigh. He checks his very gold watch. Then, in keeping with some unspoken routine, Ahmed Wali Karzai begins a ritual discussion of weather and war as they both make Kandahar a harsh place this time of year.

"Mainly the Taliban want to have an address," he explains from an armchair, "they want to show something this summer. To show they are still around. That is why there is a good need for a military operation."

I ask him if the best way to beat an insurgency is to kill.

"You have to show muscles," he says, with a fist pump. "You have to hit them hard, as hard as you can because they have no mercy for anyone."

Karzai's detractors might say the same of him. The indisputable don of Afghanistan's hostile south, he has been called a lot of things: a drug profiteer, a thug, a warlord's heavy who threatens critics (or worse). Karzai's well-nurtured notoriety spawns a list of accusations that include paying off the Taliban to grease an empire built around convoys and private security with international contracts from countries like Canada.

There is also that business of the CIA and reports that Karzai, the younger half-brother of the country's president, has been on the payroll for years in part to mount a U.S.-funded paramilitary force to kill Taliban.

Is any of it true?

"My problem is never a legal problem," says Karzai. "It's always a political problem … those international media, they are doing it for some political reason."

In the assessment of one coalition official: "Nothing in Afghanistan is clean."

Any attempt to reveal incriminating evidence against Ahmed Wali Karzai has so far failed. No government or intelligence agency has ever produced the smoking gun or least nobody has dared.

"There is always politics," Karzai says of the accusations leveled against him.

"Everybody wants to be in front. Some people, they spread rumours, they stab you in the back."

What has been proven over years is that real power in Afghanistan is less a function of government or public service than a spoil of private fiefdom. Guns, money, and control of foreign support are the true benchmarks. To that end, Ahmed Wali Karzai is unstoppable and NATO has no choice but to need him.

In diplomatic circles and among the military leadership here, the younger Karzai and his unanswered questions are distilled to the initials ‘AWK' and words like ‘issue' or ‘problem'.

"AWK is a concern," sighed a diplomat, "but he is a fact of life."

It is an open secret that the international community would like Hamid Karzai to rein him in. AWK is said to be a common worry of the U.S. president and other foreign sponsors whose countries bear the financial and human costs of the war.

Karzai the president dismisses any criticism of his brother as baseless, but at times does so at a cost to his own credibility.

"It is hard to listen to one and look at the other and be convinced of a virtuous leader," a senior official told me. When most people are asked about AWK, their opinions are shared in hushed voices on the condition they will not be named.

Among Afghans, Ahmed Wali Karzai is regarded with complementary doses of respect and fear.

On the day I visit his home, men with long beards and hard stares sit quietly in the unofficial waiting room. Their shoes -- I count 37 pairs -- are parked neatly at the steps near the door. They wait with their concerns and needs on the blue-carpeted floor until fate might yield the chance to see him. Karzai is a ‘fixer'. In Kandahar, that can mean a lot of things.

"I'm very close to the people, the tribes," says Karzai. "I earn it. I work hard… this is the major thing that I am doing is to keep these things… calm."

The Karzai hold on Afghans is firm. His control of for-hire security businesses has effectively created a private army that has thwarted the growth of a viable Afghan National Police force.

While patrolling the muddy warrens of a Kandahar neighbourhood, Canadian soldiers walked past the funeral of a young man shot dead that day in the market.

Through an interpreter a group of male relatives said he was "killed by one of AWK's men." They told the story of armed security guards looking to settle a score, and that their cousin was hit with a stray bullet.

Will they go to police? No, it's AWK, they said. They seemed shocked both by the suggestion they would utter a word and that police would actually listen.

Collaborating with Ahmed Wali Karzai is among NATO's bigger gambles in the south. Yet now, more than ever, he is crucial to the mission if it hopes to win anything close to stability in Kandahar.

In a report titled ‘Politics and Power in Kandahar', the Institute for the Study of War (www.understandingwar.org) concluded that, "Ahmed Wali Karzai's influence over Kandahar is the central obstacle to any of ISAF's governance objectives, and a consistent policy for dealing with him must be a central element of any new strategy."

Its author, Carl Forsberg, went on to predict that Karzai's behaviour and waning popularity among locals will only stir the sort of unrest and vacuum that allows space for the Taliban to exist.

Sources hint that Karzai and the need to remodel him form part of the reason why military operations slated for the summer are now effectively delayed until September.

There has been an off-the-cuff comparison to the prohibition era of 1930s America, where family cartels thrived on illicit trade and then looked to polish their image to the veneered appearance of legitimacy.

It is a trickier venture in Afghanistan. Yet it appears Ahmed Wali Karzai now sees himself as a dean of tribal dynamics and unofficial envoy to international players.

"We are winning," Karzai says, with an emphasis on the inclusive. "Taliban is no longer a movement that can threaten the stability of Afghanistan. They can create problems. But I'm not worried sitting in Kandahar with my family that the Taliban will take over."

(He claims nine assassination attempts against him in the past three years.)

In our interview that stretched nearly an hour, Karzai commended Canada for its efforts, and for bearing the challenges of serving in "the capital of Taliban and Al Qaeda." He raves especially about Brig.-Gen. Jon Vance, who has returned as Commander of Canadian Forces for a few months.

"I really hope to see General Vance," he says, "maybe he will come for lunch."

I asked Karzai if 2011 was too early for Canadian troops to be leaving Afghanistan. He explained that with 30,000 American troops here now it is no longer the concern of numbers that it was in 2006. Still, he believes it sends the wrong message about commitment, and the Taliban benefits.

"It's up to them," Karzai says of Canada's political decision-makers. "If they know the war is over they can leave. The war is still going on. War is still happening."

According to some estimates, the war has meant a billion dollar commercial network for the Karzai family through businesses dealing in food, fuel, construction, and security. Canada has one of his firms on contract to guard the Dahla Dam project.

As for being a paid operative of the CIA, Karzai never flatly denies the allegation. He says he meets with everyone -- Americans, British, Iranians, Pakistanis, Indians, Dutch.

"We are partners in this war, you know," he says. "I didn't sign a paper with a contract that I work for this agency or this person or this organization. I met with your Special Forces, I met with your military, I met with your generals. Can someone accuse me tomorrow that I was working for the Canadians?"

At the end of our discussion, Ahmed Wali Karzai wished us well. His next guests were already waiting on the couch. He checked his very gold watch and shifted his attention. We left Karzai's villa, walking past the barefoot men still waiting, and returned to the weather and war that make Kandahar a harsh place this time of year.