Baghdad ? Amid tears and wails, mourners in the southern city of Najaf on Tuesday began burying victims from a suicide bombing that killed nearly 50 worshippers and injured dozens of others just before evening prayers Monday in nearby Karbala.

In Baghdad, a long-anticipated Iraqi national reconciliation conference began with great fanfare, then quickly dissolved into the usual sectarian and political stalemates that have marred several similar gatherings in recent years.

But Vice President Dick Cheney gave an upbeat view of conditions in Iraq as he concluded his unannounced trip to mark the fifth anniversary of the U.S.-led invasion. Cheney also defended the toppling of Iraqi dictator Saddam Hussein as part of the struggle against terrorism following the Sept. 11 attacks on the World Trade Center and the Pentagon.

This month, an exhaustive Pentagon-sponsored review of more than 600,000 Iraqi documents captured during the 2003 U.S. invasion found no evidence that Saddam’s regime had any operational links with the al-Qaida terrorist network.

But Cheney, who spent the night at a sprawling U.S. base in the northern town of Balad, told soldiers they were defending future generations of Americans from a global terror threat.

“This long-term struggle became urgent on the morning of Sept. 11, 2001. That day we clearly saw that dangers can gather far from our own shores and find us right there at home,” said Cheney, who was accompanied by his wife, Lynne, and their daughter Elizabeth.

“So the United States made a decision: to hunt down the evil of terrorism and kill it where it grows, to hold the supporters of terror to account and to confront regimes that harbor terrorists and threaten the peace,” Cheney said. “Understanding all the dangers of this new era, we have no intention of abandoning our friends or allowing this country of 170,000 square miles to become a staging area for further attacks against Americans.”

Cheney later traveled to Irbil, the capital of the mostly autonomous Kurdish region, for a meeting with Kurdish leader Massoud Barzani, before flying to Oman.

Monday’s devastating security breach at one of Iraq’s most sacred places added to the pressure on Prime Minister Nouri al-Maliki to make recent security gains stick and to keep the country on track for October elections.

The Baghdad reconciliation conference was intended to bring the country’s warring factions to the negotiating table.

But only half of the 700 invited guests showed up, and any real chance for negotiations dissolved when both the leading Sunni Muslim bloc and the powerful faction loyal to the rebel Shiite Muslim cleric Muqtada al-Sadr announced boycotts.