U.S. military officials are accusing the highest levels of the Iranian government of sending sophisticated roadside bombs to Iraq that have killed 170 coalition troops since 2004. On Sunday, reporters in Baghdad received an unusual briefing on the allegations. The news conference was led by three U.S. military officials who refused to be quoted by name. No TV cameras or tapes were allowed in, and journalists’ cellphones were taken away before they entered the briefing room. Iran is denying the charges. One Iranian official said, “We ask those who are claiming such evidence: Show the documents in public.” The bomb allegations first appeared on Saturday in a front-page article written by Michael Gordon titled “Deadliest Bomb in Iraq Is Made by Iran, US Says.” The article relied almost entirely on unnamed government sources. Several media critics compared the piece to Gordon’s articles from 2002 alleging Iraq had weapons of mass destruction.

Meanwhile, Newsweek is reporting that at least one former White House official contends that some Bush advisers secretly want an excuse to attack Iran. The administration’s former National Security Council director for Iran and Persian Gulf affairs, Hillary Mann, said: “They intend to be as provocative as possible and make the Iranians do something [America] would be forced to retaliate for.” Newsweek is also reporting that the U.S. is likely to send a third Navy carrier to the Persian Gulf. This comes as The Guardian newspaper reports U.S. preparations for an airstrike against Iran have reached an advanced stage. The present military build-up in the Gulf would allow the U.S. to mount an attack by the spring.

The Washington Post reports that at a recent meeting, Vice President Cheney’s national security adviser, John Hannah, said 2007 is “the year of Iran.”

Illinois Senator Barack Obama has formally launched his presidential campaign. If elected, the Illinois Democrat would become the country’s first African-American president. On Saturday, Senator Obama addressed thousands of supporters at the Old State Capitol in Springfield, Illinois — the site of Abraham Lincoln’s famous “House Divided” speech against slavery in 1858. Senator Obama called for the withdrawal of all U.S. combat troops from Iraq by March 2008.

Sen. Obama: “Most of you know that I opposed this war from the start. I thought it was a tragic mistake. Today we grieve for the families who’ve lost loved ones, the hearts that have been broken, the young lives that could have been. America, it’s time to start bringing our troops home. It’s time. It’s time to admit that no amount of American lives can resolve the political disagreement that lies at the heart of someone else’s civil war.”

Senator Obama’s call for a withdrawal of U.S. troops was quickly attacked by Australian Prime Minister John Howard.

John Howard: “If I were running al-Qaeda in Iraq, I would put a circle around March 2008 and pray as many times as possible for a victory not only for Obama but also for Democrats.”

On Sunday, Senator Obama responded.

Sen. Obama: “Mr. Howard may have quibbles with our intelligence estimates; maybe he has better ones. I would also note that we have close to 140,000 troops on the ground now, and my understanding is that Mr. Howard has deployed 1,400. So if he’s ginned up and wants to fight the good fight in Iraq, I would suggest that he calls up another 20,000 Australians and sends them to Iraq.”

In other political news, Democratic presidential candidate Senator Hillary Clinton is continuing to refuse to acknowledge she made a mistake in voting for the Iraq War. On Saturday, during a town hall meeting in New Hampshire, a local resident named Roger Tilton questioned her.

Roger Tilton: “I want to know if right here, right now, once and for all and without nuance, you can say that war authorization was a mistake. I, and I think a lot of other primary voters, until we hear you say it, we’re not going to hear all the other great things you are saying.”

Sen. Hillary Clinton: “Well, I have said, and I will repeat it, that knowing what I know now, I never would have voted for it. But I also (applause) — I mean, obviously you have to weigh everything as you make your decision. I have taken responsibility for my vote. The mistakes were made by this president, who misled this country and this Congress into a war that should not have been waged.”

In Iraq, at least 80 people died earlier today in three bombings in central Baghdad; 150 other people were injured. The blasts occurred on the first anniversary of the bombing of the important Shiite Golden Dome shrine in Samarra. One of the bombs blew up today shortly after the Iraqi government called for a 15-minute period of silence to commemorate last year’s bombing.

On Capitol Hill, the House begins debate today on a nonbinding resolution opposing President Bush’s escalation of the war. A vote is expected this week.

General David Petraeus has taken charge of U.S. forces in Iraq, becoming the third commander in the war. He said the American task is now to help Iraqis “save the country.”

Gen. Petraeus: “The challenges ahead are substantial. The rucksack of responsibility is very heavy. In truth, it is too heavy for any one person to bear, and we will all have to share the burdens and move forward together. And if we can do that, and if we can help the people of Iraq do likewise, then the prospects for success are good. Failing that, Iraq will be doomed to continuing violent and civil strife, and surely that is a prospect that all must strive to avoid.”

Meanwhile, the former head of the National Security Agency is warning victory is no longer an option in Iraq. Writing in The Washington Post, General William Odom said the Bush administration must recognize that fighting on simply prolongs U.S. losses and blocks the way to a new strategy. Odom writes that getting out of Iraq is the precondition for creating new strategic options. Odom also accuses the Bush administration of pushing policies that are destabilizing the Middle East.

Democratic Senator Carl Levin has announced plans to continue to investigate how dubious intelligence linking Saddam Hussein to the September 11 attacks became part of the justification for the 2003 invasion of Iraq. On Friday, the Pentagon’s inspector general accused former Pentagon official Douglas Feith of inappropriately manipulating intelligence on Iraq. Feith appeared on Fox News Sunday with Chris Wallace.

Douglas Feith: “Nobody in my office ever said there was an operational relationship between Iraq and al-Qaeda. It’s just not correct. I mean, words matter. And — and people are throwing around loose allegations, vague allegations based on not reading the words carefully.”

Chris Wallace: “I’m just taking comments from your PowerPoint. You said some indications of possible Iraqi coordination with al-Qaeda specifically related to 9/11. You said that the Atta meeting in Prague 2001 was a known contact.”

Douglas Feith: “The people who did that briefing were taking the position that the intelligence community took originally. The CIA later changed its views on that meeting, after the time relevant here.”

U.S. forces in eastern Afghanistan have launched artillery rounds into Pakistan, reportedly in an effort to strike Taliban forces. The attack came just ahead of a visit to Pakistan by Defense Secretary Robert Gates. He is meeting with Pakistani President Pervez Musharraf.

Palestinian Prime Minister Ismail Haniyeh of Hamas said his government plans to step down as early as this week following the agreement by Hamas and Fatah to form a coalition government. Haniyeh will retain the post of prime minister.

Harvard University has named Drew Gilpin Faust as the school’s new president. Faust is the first woman to head the university. She is a noted scholar of the American South and was dean of Harvard’s Radcliffe Institute for Advanced Study. Half of the eight Ivy League schools are now run by women.

British billionaire Richard Branson has offered a $25 million prize for the scientist who discovers a way to extract greenhouse gases from the atmosphere.

Richard Branson: “So the challenge Al Gore, James Lovelock, Jim Hansen, Sir Crispin Tickell, Tim Flannery and myself are laying down to the world’s brightest brains is to devise a way of removing greenhouse gases, at least the equivalent of one billion tons of carbon per year and hopefully much more. And you will have the satisfaction of saving thousands of species and possibly even mankind itself.”

Richard Branson made the announcement alongside former Vice President Al Gore.

Al Gore: “It’s a challenge to the moral imagination of humankind to actually accept the reality of the situation we are now facing.”

Egyptian authorities have released from prison a Muslim cleric who was kidnapped off the streets of Italy by CIA agents three years ago. The cleric, Abu Omar, was abducted as part of the Bush administration’s program known as extraordinary rendition. The cleric has accused Egyptian agents of beating him and torturing him with electric shocks.

In Somalia, at least three people have died after five mortar bombs struck northern Mogadishu overnight. Several homes were flattened in the attacks.

The U.S. government is resuming broadcasts today of Somali-language programs in the Horn of Africa for the first time in 13 years. One Somali website criticized the broadcasts as a tool for the U.S. to disseminate propaganda and a “means of promoting U.S. foreign policy based on pure colonialism.” The Voice of America programs are beginning as the U.S. military expands its presence in Africa. The United States recently backed Ethiopia’s invasion of Somalia, and U.S. fighter planes have bombed Somalia at least twice since January. Last week President Bush announced the Pentagon would create a new African command to coordinate U.S. military operations throughout the continent.

The Federal Emergency Management Agency has agreed to pay about $3 million to help repair the former home of Confederate President Jefferson Davis. Davis led the Confederacy in the South during the Civil War. Hurricane Katrina nearly destroyed the 150-year-old home in Biloxi, Mississippi.

In New Orleans, low-income residents are still fighting to prevent their homes from being demolished. On Saturday, some residents of the Central City public housing complex defied government orders and moved back into their old apartments. The city is planning to demolish four large public housing developments even though tens of thousands of low-income New Orleans residents remain displaced.

And in South Africa, thousands gathered on Saturday for the funeral of longtime anti-apartheid activist and freedom fighter Adelaide Tambo. She recently died at the age of 77. At her funeral, former South African President Nelson Mandela said, “She was a mother to the liberation movement in exile and a nationally revered figure in our new nation.” Her late husband, Oliver Tambo, led the African National Congress in exile.