NEW YORK — After two years of study, a panel of top scientists and military specialists working for the National Research Council has concluded that the nation’s protections against missile attack suffer from major shortcomings, leaving the United States vulnerable to certain kinds of long-range strikes.
In a report, the panel suggested that President Obama shift course and expand a system inherited from President George W. Bush, setting aside parts of an antimissile strategy he initiated in 2009. By doing so, the panel said, the nation’s defenses would be better prepared to defeat the long-range missiles the report suggests Iran may be developing.
It is the first time the research council — an arm of the National Academy of Sciences, chartered by Congress to give scientific and technical advice to the government and considered the nation’s preeminent group of scientists — has weighed in on the nation’s overall plans for defeating missile attacks.
‘‘For too long, the US has been committed to expensive missile defense strategies without sufficient consideration of the costs and real utility,’’ said L. David Montague, the panel’s cochairman and a retired president of Lockheed Martin Missiles and Space. The Pentagon must strengthen its technical analyses, he added, so it ‘‘can better evaluate new initiatives.’’
Montague, an engineer by training, is an independent consultant and one of the few members of the 16-person panel whose roots lie in the defense industry. The others are scientists, engineers, and weapons specialists from universities, think tanks, and national laboratories, including the nuclear weapons lab at Livermore, Calif.
The report comes as worries rise over fears Tehran might develop warheads for its growing fleet of missiles.
In its highly technical, 260-page report, the panel recommends an overhaul that would make the antimissile system ‘‘far more effective,’’ including new sensors and interceptors, and an additional base for interceptors in Maine or New York; existing ones are in California and Alaska.
The report calls the plan affordable, saying it could fit within current antimissile spending — which runs about $10 billion a year — if the military eliminated what the panel describes as costly and unneeded systems.
The assessment is a major blow to Obama’s strategy of playing down the long-range defenses he inherited from Bush and focusing instead on defenses in Europe against shorter-range Iranian missiles. He articulated the shift in September 2009, calling the envisioned system ‘‘stronger, smarter, and swifter.’’
But the report, released Tuesday, faults the results of this strategy as weak. It says the domestic defenses currently in place can probably handle crude missiles fired from North Korea, but it criticizes the antimissile arms as ‘‘fragile’’ and full of ‘‘shortcomings that limit their effectiveness against even modestly improved threats.’’
The report gives Obama’s European shift conditional approval if planned advances materialize. But it recommends that the plan’s final phase — intended to protect the United States from long-range Iranian missiles — be scrapped in favor of the panel’s proposal for a stronger domestic system.
In short, the panel would undo part of Obama’s shift and strengthen Bush’s antimissile approach, creating more of a hybrid.
Philip E. Coyle III, a former national security official in the Obama White House and former director of weapons testing at the Pentagon, said the panel’s report revealed an antimissile proclivity for ‘‘producing and fielding hardware rather than facing up to physical realities.’’
The report comes as worries rise over Iran’s nuclear program and fears that Tehran might one day decide to develop warheads for its rapidly growing fleet of missiles. Today, its missiles are short and medium range. The new report looks ahead a decade or more to what it calls the ‘‘likely development’’ of Iranian missiles designed to rain warheads down on the United States.
Since the 1980s, when President Reagan began the modern hunt for defenses against long-range missiles, Washington has spent more than $200 billion devising ways to zap incoming enemy warheads that move at speeds in excess of four miles per second. Critics have long ridiculed the aim as delusional, saying that any country smart enough to make intercontinental ballistic missiles could also make simple countermeasures sure to foil any defense.
In a nod to critics, the new report identifies enemy countermeasures as the main obstacle of the domestic antimissile system, with many of its recommendations aimed at creating improved technologies to meet the challenge.