A military base in or near the city of Caribou could be the nation’s last line of defense against ballistic missile threats from around the world if the findings of a study by the National Academy of Sciences ever come to fruition.

The National Research Council, a branch of the National Academy that includes scientists, engineers and high-level military experts, concluded in a 260-page report released Tuesday that there are troubling and potentially disastrous holes in the U.S. missile defense system, including in the northeastern part of the country. It identified Fort Drum or Rome, N.Y., or the Aroostook County city of Caribou as ideal sites for facilities designed to intercept long-range missiles from hostile countries such as North Korea or Iran as they approach targets in the United States. The strategy would replace efforts by the Obama administration to center the system in Europe and over the oceans.

The defense vulnerability of the northeastern United States is an issue that has long been debated in Maine, particularly during past deliberations about whether to close military facilities here.

Loring Air Force Base in Limestone, a Strategic Air Command base with a mission of defending the United States against the Soviet Union, was closed in 1994. Limestone and Caribou are neighboring communities.

In 2005, the Department of Defense opted to close Brunswick Naval Air Station in midcoast Maine, which was seen by some as a Cold War-era facility that housed squadrons of P-3 Orion reconnaissance aircraft. BNAS closed officially last year when the squadrons completed their move to Jacksonville, Fla.

Decommissioned Air Force over-the-horizon backscatter radar sites, which aimed to detect Soviet bombers attacking the U.S. by coming across the northern polar regions, are located in remote eastern and western Maine. One near Columbia Falls in Washington County is being eyed by the Passamaquoddy Tribe for a wind farm. Last year, a former radar site in Moscow was sold to a Portland-based real estate firm for $730,000.

Sen. Susan Collins, ranking Republican on the Homeland Security Committee and member of the Senate Armed Services Committee — in addition to being a Caribou native — said in a written statement Tuesday evening that her concern that the eastern United States is adequately protected is nothing new.

“Nearly 60 percent of the U.S. population lives east of the Mississippi River,” said Kevin Kelley, a spokesman for Collins. “Senator Collins has long been concerned that this region of our country be equally protected against ballistic missiles.”

Kelley said Collins sees the merits and flexibility of the mostly sea-based approach favored by Obama but fears, in particular, advanced long-range missile technology thought to be under development in Iran.

“[The report] should serve as a warning that the administration needs to reassess its defenses,” reads the statement from Collins, who said she will urge the chairman of the Senate Armed Services Committee to hold a hearing to evaluate the panel’s conclusions and recommendations.

The National Research Council’s exhaustive report, “Making Sense of Ballistic Missile Defense: An Assessment of Concepts and Systems for U.S. Boost-Phase Missile Defense in Comparison to Other Alternatives,” focuses on the science and engineering behind an effective missile-defense system capable of protecting against missiles in all phases of flight. It does not address policy issues around missile defense, including its effect on U.S. military and foreign policy.

The highly technical report questions whether a current system that emphasizes intercepting missiles from countries such as Iran and North Korea soon after they are launched is effective enough when paired with existing systems designed to shoot down the missiles near the end of their trajectories. One recommendation among several is the installation of new missile-interceptor equipment in the northeastern United States that is capable of using existing radar technology.

Christopher Cousins

Christopher Cousins has worked as a journalist in Maine for more than 15 years and covered state government for numerous media organizations before joining the Bangor Daily News in 2009.