The independent, non-partisan group, Physicians for Social Responsibility, is urging the U.S. government to become better prepared for the possibility of a major nuclear attack in the United States. The organization, which won a Nobel Peace Prize in 1985, works to eliminate nuclear weapons worldwide and to address their effects on public health.

In a report issued Thursday, Physicians for Social Responsibility warns that the United States is not prepared for nuclear terrorism.

For starters, Ira Helfand, who co-authored the report, says there are many basic questions the U.S. government still needs to answer.

"At this time, the United States does not have in place a plan for deciding, in the event of a nuclear attack, and then taking into account prevailing weather conditions, whether to evacuate people, or whether to shelter them in place," said Ira Helfand. "We do not have anyone designated to make that decision. We do not have clear criteria established to guide the making of that decision. There is no plan to communicate that decision to the public."

The new report comes as the United States marks two somber anniversaries - one year since Hurricane Katrina devastated the U.S. Gulf coast and five years since the September 11 terror attacks.

Irwin Redlener, from Columbia University's National Center for Disaster Preparedness, says the September 11 events showed that the United States was not prepared for what he termed "mega-disasters." He added that Hurricane Katrina, one year ago, revealed continuing inadequacies in the U.S. government's ability to respond to disasters.

"Not only were we not prepared, we were not, in fact, as competent as many of us thought we would have been or should be, in terms of responding to a natural disaster, no less the scale of what would happen with nuclear terrorism, which, by the way, would dwarf everything that the United States has ever seen in its history," said Irwin Redlener.

Redlener said that since the September 11, 2001 attacks, the U. S. government has spent tens of billions of dollars on homeland security and disaster preparedness. He said there is a lack of accountability as to where the money has gone and that the improvements made have been piecemeal.

"Yes, we've spent money," he said. "We've spent freely and wildly. What we've accomplished is many, many acts of preparedness, rather than a whole cloth of a country that should be safer and could have been safer."

Since September 11, 2001, U.S. officials have emphasized the need to protect the American people from terrorism. The report's co-author Helfand urged the U.S. government to match those words with more effective preparation, or take some of the blame for the negative effects of a potential future attack.

"If there is a nuclear terrorist attack, the responsibility for the dead and the dying will rest, not only with those who perpetrate the attack, but with those in our government who have been negligent in preparing for it," said Ira Helfand.

Helfand said Physicians for Social Responsibility has shared its report with officials in the Department of Homeland Security. He added that the group also has sent copies to every member of Congress.