Afghan President Hamid Karzai confirmed Tuesday that his powerful half-brother, Ahmed Wali Karzai, had been assassinated in one of his Kandahar homes. The Taliban quickly claimed responsibility for the killing, calling it "one of our biggest achievements." Security experts questioned whether the Islamist militant group was really responsible — according to some conflicting reports, Ahmed Wali Karzai was shot by a trusted family associate, who was then killed by his victim's body guards. How will the death of such an influential government insider affect the Afghan war?

This assassination gives the Taliban a huge boost: No matter who was really behind the killing of Ahmed Wali Karzai, says Arvind Ramakrishnan in Britain's Telegraph, it's bound to "damage public confidence" in Hamid Karzai's government. His staunchly pro-U.S. half-brother was the "de facto governor of Kandahar," eclipsing the importance of the real governor. His many businesses included security firms that have helped the U.S. hunt down insurgent leaders, so this assassination marks "an enormous propaganda and moral boost for the Taliban."
"Ahmed Wali Karzai assassination 'huge propaganda boost for Taliban'"

The killer might actually have helped the Afghan government: The assassination weakens Hamid Karzai's hand as he fights the Taliban for control of Kandahar, says Juan Cole at Informed Comment. That opens the door to greater instability in southern Afghanistan. But "Ahmed Wali Karzai was a warlord of sorts" and a suspected drug trafficker, so his demise could open the way to a less corrupt government.
"Ahmed Wali Karzai killing points to more instability"

It's unclear how this assassination affects the war: Ahmed Wali Karzai "ran militias on behalf of the CIA," says Max Fisher in The Atlantic, "and funded drug networks that were the stated enemy of the U.S. military." He was "a close ally of the U.S. and a tremendous drag on its mission to win over the Afghan people." His death, and our uncertainty about how it affects the war, is a reminder of how dangerous it is to rely on the Afghan political system to establish peace when it's such a big part of the country's problems.
"Ahmed Wali Karzai was a symbol of Afghan war's complexity"