U.S. soldier, Afghan security forces and a villager in Kandahar. (U.S. Army / April 21, 2011)

Twenty-five foreign militants who had just trespassed from Pakistan into Afghanistan were killed Tuesday by Afghan and NATO troops in what Reuters deemed was "the first sign of retaliatory attacks in Afghanistan after al Qaeda leader Osama bin Laden was killed."

Fighting across Afghanistan between NATO and insurgents such as the Taliban and al Qaeda intensified over the weekend with the official beginning of the annual post-winter fighting season. The death of Bin Laden heightens the stakes.

"We are aware of the situation here now that al Qaeda and other elements will try to infiltrate into Afghanistan. We have launched an operation to control border infiltration," an Afghani provincial governor said.

On the other side of Afghanistan, a NATO airstrike killed five private security guards for a reason that remains unclear. Insurgents, including a 12-year-old suicide bomber, killed six people on Sunday.

President Barack Obama has pledged to start in July a three-year-long pullout of the 100,000 American troops in Afghanistan. Senate Foreign Relations Committee Chairman is expected to meet later this week with Afghan President Hamid Karzai on the subject--exactly two years after President Barack Obama met with Karzai and Pakistani President Asif Ali Zardari about weakening the Taliban and al Qaeda.

Yet, the progress has been slow, wrote Kerry in an op-ed on Sunday.

"The [Afghan] army is dominated by ethnic Tajiks and veterans of the Northern Alliance, with few officers from the Pashtuns, who are the country’s largest ethnic group and comprise the majority of the Taliban," he said.

The Taliban have refused to negotiate until all foreign troops are gone. But NATO is afraid of pulling out because the Afghan security forces alone would be not match for the Taliban.

"The death of Osama will not put pressure on the Taliban to negotiate," said a Taliban leader. "The Taliban are an Afghan movement, while al Qaeda is an international organization."

Then there's the corruption in the Karzai regime that has repeatedly drawn criticism from Kerry and the questions about India's role in the region.

"Deep-seated Pakistani suspicions of Indian aspirations in Afghanistan and strong anti-American sentiment have made it difficult for Pakistan’s leaders to take sufficient action against the Taliban and other groups that target the US and coalition forces," Kerry said. "We must continue working with our allies in Pakistan to remove these sanctuaries to have a chance of success across the border."

“Pakistan is the problem, and the West has to pay attention,” Afghanistan's former intelligence director told the New York Times. "[The United States must] wake up to the fact that Pakistan is a hostile state exporting terror.”

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