The Pentagon would have to decide whether a combat-ready Pacific Missile Range Facility on Kauai would protect either Hawaii or the mainland against a possible North Korean ballistic missile attack, because the missile defense system there would not be capable of shielding both, an East-Asia security analyst said Friday.

The idea to convert the Pacific Missile Range testing facility at Barking Sands into a combat-ready base has gained renewed interest since North Korea conducted its fourth nuclear test Jan. 6, Reuters reported, citing unidentified sources.

But even with a beefed-up military presence, an arsenal of missiles and an additional $41 million annually pumped into Barking Sands, no single system can intercept both a missile aimed directly at the islands and also have the capability to hit a ballistic missile flying possibly hundreds of miles overhead as it wings toward the continent, said Denny Roy, an East Asia security specialist at the East-West Center.

“Those are two completely different systems,” Roy said. “There’s no one system that does everything from zero feet to possibly hundreds of miles in the atmosphere. Would the system be intended to intercept very, very high-flying missiles from the rim of Asia to the U.S. homeland, or would it be used to protect the islands as they (missiles) make their way down?”

U.S. REP. Mark Takai of Hawaii, who sits on the House Armed Services Committee, wrote in an email to the Honolulu Star-Advertiser, “The AEGIS Ashore Missile Defense Complex in Kauai is vital to our national defense strategy in the Asia-Pacific. Keeping this asset at the Pacific Missile Range Facility is the best way to ensure we have protection for Hawaii’s critical defense infrastructure against increasingly belligerent actors that threaten our country. Through my role on the House Armed Services Committee, I will continue to work to ensure resources are available to support our defense posture in both Hawaii and the larger region.”

Reuters cited an unidentified source who said the Missile Defense Agency wrote a classified report to Congress in September 2014 that explored the idea of putting the Pacific Missile Range facility into “full operation.”

The Pacific Missile Range completed its first Aegis Ashore intercept test in December, Reuters said. The test used a Raytheon Standard Missile-3 Block 1B to destroy a target that replicated an Iranian Ghadr-110 medium-range missile, Reuters said.

The test showed that two different Raytheon missiles could hit a target both inside and outside the atmosphere, Reuters said.

A land-based Aegis missile system on Kauai would serve as a more reliable defense compared with existing sea-based Aegis systems on Navy destroyers that might not always be in the area to intercept incoming ballistic missiles, Roy said.

Whether the Pentagon’s idea for Barking Sands proceeds, he said, reports of the discussions are sending a clear message to North Korea, as well as to China, North Korea’s strongest ally.

“Part of this is strategic and it’s all about military capabilities,” Roy said. “But another major part is psychological. It’s both potentially reassuring to the American public and also a signal to North Korea that you’re not gaining any security or influence by deploying nuclear weapons. Our message to the American public would be that it’s strictly defensive. But in military strategy there’s nothing that’s purely defensive.”