KABUL, Afghanistan (AP) — Afghan President Hamid Karzai, who for years pushed for reconciliation with the Taliban, now says attempts to negotiate with the insurgent movement are futile and efforts at dialogue should focus instead on neighboring Pakistan. The Afghan leader explained in a videotaped speech released by his office Saturday that he changed his views after a suicide bomber, claiming to be a peace emissary from the insurgents, killed former Afghan President Burhanuddin Rabbani at his home on Sept. 20. Rabbani was leading Karzai's effort to broker peace with the Taliban. "Their messengers are coming and killing. ... So...