One of the nation's preeminent scientists is speaking out for the first time about what he says is the government's failure to coordinate preparations and response plans in the case of a biological attack or naturally occurring pandemic.

Dr. D.A. Henderson, the epidemiologist who led the global effort to eradicate smallpox and is a leading voice on biodefense, told The Huffington Post that no one is in charge when it comes to dealing with the fallout from a bioterrorism attack.

"I've kept quiet about this for a long time, but I'm deeply concerned," said Henderson, who was named chief of a new Office of Public Health Preparedness in the Department of Health and Human Services soon after the 2001 anthrax attacks.

In a preview of a speech he plans to make later this month at the Public Health Preparedness Summit in Anaheim, Calif., Henderson said that a decade of work to ramp up the nation's biodefenses on the local, state and federal levels has not resulted in an overall strategy on what to do in the critical hours after an attack is detected.

Should officials launch a mass evacuation? Advise people to stay home and "shelter in place"? For how long? And who should receive medical countermeasures such as vaccines and antibiotics -- emergency workers and those in the vicinity of an outbreak, or everyone? The 2001 anthrax attacks killed five people and prompted 30,000 people to be treated with antibiotics, Henderson said. Public health and homeland security officials have said they worry a much larger attack could engulf an entire city, killings hundreds of thousands and requiring treatment for millions more.

"This has been discussed for years. It's still not decided -- what do we recommend?" said Henderson, who was a 2002 recipient of the Presidential Medal of Freedom, the nation's highest civilian honor. "Nobody is really in charge. Somebody has got to take the lead."

The Obama administration launched in 2009 a "National Strategy for Countering Biological Threats," which emphasizes the need for all sectors of society to coordinate their response in an emergency. But Henderson said "they're not" coordinating. "Part of it is it's complicated. There's inertia."

This isn't the first time red flags have been raised about how unprepared the nation is to counter a biological emergency. In October, the Bipartisan WMD Terrorism Research Center issued a Bio-Response Report Card that gave failing grades to the nation with regard to its readiness to deal with a large-scale pandemic. That same month, The New York Times magazine published an article that depicted a biodefense establishment disorganized to the point of dysfunction. Dozens of agencies and officials have some involvement in biodefense, yet no one person or department oversees them all, the magazine reported. Inter-agency back-biting and finger-pointing are common, as are politically suspect decisions that may have compromised the nation's stockpile of life-saving vaccines and medical countermeasures, the article said.

Randall Larsen, the head of the WMD Center who famously slipped a vial of anthrax-like weaponized powder past White House guards a few days after 9/11, said it is impossible to prevent a biological attack. The only defense is quick action to mitigate the damage, he said.

Henderson agrees. But he also despairs that when the time comes -- as most experts say it will -- the nation will not be ready.

"I've come to the point I really have to talk about it," he said. "We've really got to crack this thing loose and get people on it. They will say they have the report, the plan is made, it's ready to go. That's what I was told a year and half ago."