US officials have confirmed what many have widely feared: the BP oil spill in the Gulf of Mexico is the worst oil spill in US history. On Thursday, the US Geological Survey said the well has been spewing between 504,000 and more than a million gallons of oil a day. That means a minimum 19 million gallons have spilled into the Gulf over the past five weeks, easily surpassing the size of the 1989 Exxon Valdez disaster in Alaska. The highest estimate would mean a spill of nearly 39 million gallons.

The news comes as BP continues its “top kill” operation to stop the spill by pumping heavy drilling mud and cement into the breached mile-deep well. On Thursday, BP said the procedure was going well but then later announced it had been suspended for eighteen hours. BP has since resumed the effort and says it hopes to determine this weekend whether it’s succeeded.

Marine scientists, meanwhile, have discovered what they say is a massive new plume of oil stretching twenty-two miles beneath the Gulf, the second such discovery since the spill. Experts believe the plume resulted from the toxic dispersants used by BP to break up the oil. In contrast to the first, the new plume is headed inward toward the habitats of many fish and other species. On Thursday, oceanographer Ian MacDonald of Florida State University said BP has been minimizing the size of coastal areas affected by the spill.

Ian MacDonald: “I cannot understand why BP persists in making these claims on television that are so patently false and so easily disproved. I mean, don’t they have PR people telling them that the best thing to do is to fess up and admit what they have to do. I mean, this is absolutely shocking, and I can’t believe that they are persisting in this.”

The Obama administration, meanwhile, has formally announced its suspension of oil exploration off the Alaskan coast as well as of lease sales in Virginia and the Gulf of Mexico. On Thursday, President Obama also said he would extend the moratorium on new deepwater drilling permits for six months and halt operations at thirty-three deepwater wells in the Gulf of Mexico. Obama is heading to the Gulf Coast today in his second visit to the region since the disaster began. In his first news conference in ten months, Obama defended his administration’s response to the spill.

President Obama: “As far as I’m concerned, BP is responsible for this horrific disaster, and we will hold them fully accountable on behalf of the United States as well as the people and communities victimized by this tragedy. We will demand that they pay every dime they owe for the damage they’ve done and the painful losses that they’ve caused. Those who think that we were either slow on our response or lacked urgency don’t know the facts. This has been our highest priority since this crisis occurred.”

The political fallout from the spill continued Thursday with the resignation of the head of the government agency responsible for regulating offshore drilling. Elizabeth Birnbaum’s departure from the Minerals Management Service follows several damning revelations about her agency, including the news that it exempted BP from a comprehensive environmental review of the project that led to the spill. Although Birnbaum formally resigned, multiple news outlets are reporting she was fired.

Scrutiny meanwhile is increasing on the ties between BP and Energy Secretary Steven Chu. In 2007, BP awarded the bulk of a $500 million grant to the University of California, Berkeley laboratory where Chu was then director. Chu has worked closely with BP executives in the aftermath of the spill. BP’s former chief scientist, Steven Koonin, now works directly with Chu as undersecretary of energy for science. Koonin has been recused from any involvement with the spill response because of his BP ties.

The House has approved a measure that would allow the Pentagon to repeal the ban on openly gay and bisexual servicemembers known as “Don’t Ask, Don’t Tell.” The repeal would require approval of top military commanders following the completion of an internal review due by December 1st. The measure was attached to the annual Pentagon policy bill by a vote of 234 to 94. The overall bill is expected to come up for vote today. The House move came shortly after the Senate Armed Services Committee approved a similar measure backing the repeal.

In other news from Capitol Hill, the Senate has approved a nearly $60 billion measure in continued funding for the wars in Iraq and Afghanistan. The measure includes full funding for President Obama’s deployment of an additional 33,000 troops in his escalation of the Afghan war. In earlier voting, the Senate rejected an amendment from Democratic Senator Russ Feingold that would have required President Obama to submit a timetable for a US withdrawal from Afghanistan.

A flotilla of nine aid ships is approaching the Gaza Strip through the Mediterranean Sea in an attempt to break the Israeli blockade and deliver over 10,000 tons of humanitarian goods. Israel has vowed to block the fleet and has prepared a prison for the over 750 passengers aboard the vessels. Organized by the Free Gaza Movement, the flotilla is the largest to attempt to breach the Gaza blockade since Israel imposed it three years ago. Israel has forcefully stopped at least three other Free Gaza sailings since January 2009.

The Israeli government meanwhile continues its crackdown on Palestinian activists who campaign for the equal treatment for Israel’s Arab citizens. On Thursday, Ameer Makhoul of the Popular Committee for the Defense of Political Freedom inside Israel was charged with espionage for allegedly providing intelligence to the Shiite group Hezbollah. Another Palestinian activist, Dr. Omar Said, has also been charged with spying for Hezbollah. The Israeli government’s case appears to rest almost entirely on Makhoul and Said’s testimony while in Israeli custody, where their families claim they were tortured and abused.

A top United Nations official is preparing to urge the Obama administration to end CIA drone strikes on alleged militant suspects abroad. In an interview with the New York Times, Philip Alston, the United Nations Special Rapporteur on Extrajudicial, Summary or Arbitrary Executions, said he will issue a report next week concluding that drone attacks should be in the hands of regular armed forces, not intelligence agencies. Alston says he’s based his call in large part on the complete absence of accountability for CIA attacks. A recent report from the New America Foundation found nearly one in three people killed by CIA drone attacks in Pakistan is a civilian. The US is believed to have carried out as many as 100 drone attacks in Pakistan since 2008, the majority since President Obama took office.

The Obama administration has released its first National Security Strategy since taking office. The document calls for boosting multilateral cooperation and strengthening international institutions and treaties. But in language echoing the Bush administration on the use of force, the document asserts “the United States must reserve the right to act unilaterally.” Speaking in Washington, Secretary of State Hillary Clinton said “values” are at the core of US national security policy.

Secretary of State Hillary Clinton: “Values matter to our national security. It should go without saying, but it needs to be not only repeated but perhaps emblazoned as a set of principles that are guiding us. Democracy, human rights, development are mutually reinforcing, and they are deeply connected to our national interests.”

A group of indigenous activists have traveled to Denver this week to protest a uranium mining conference discussing new mining projects on Navajo land. Three Navajo activists were removed from the conference despite being formally invited to attend one of the sessions. On Thursday, one of the three, Nadine Padilla of the Multicultural Alliance for Safe Environments, protested her expulsion.

Nadine Padilla: “The problem is this is a meeting we should have been involved in from the start. The four proposed mines on Navajo land is something the community members need to be a part of. We need to be at the table and need to have our voices and our concerns heard by people who are making the decisions, such as the federal agencies like the Nuclear Regulatory Commission.”

And in Peru, the American activist Lori Berenson has been freed on parole after nearly fifteen years behind bars. Berenson was convicted in 1996 by hooded Peruvian military judges of collaborating with the rebel group MRTA. She has long maintained her innocence. Berenson had no comment for the media Thursday as she was rushed out of a Lima prison. But shortly before her release, Berenson’s father, Mark Berenson, welcomed the newfound freedom for his daughter and her one-year-old son Salvator.

Mark Berenson: “I’m just happy that Lori and Salvador will be free, that justice has been served in Peru. It’s been fourteen-and-a-half years that we have waited for this moment, and that’s about all we can say now.”

Lori Berenson will be required to remain in Peru under the terms of her five-year parole.