WASHINGTON -- A Democratic lawmaker urged the Pentagon Monday to boost its missile defense system before North Korea develops the capability to strike the US mainland with nuclear weapons.

In a contribution to The Hill, Rep. Ted Lieu (D-CA) underscored the urgency of tackling North Korea's missile and nuclear threats with action, not words.

"President Trump's lack of a comprehensive strategy and reckless war of words with North Korea has sent the world into a panic," he wrote. "But all the provocative talk in the world won't change the fact that the Hermit Kingdom is a nuclear power and will soon have the nascent capability to strike the US mainland. We need to dramatically shift our thinking as to how to tackle this new reality."

North Korea test-fired two intercontinental ballistic missiles in July, claiming the entire US mainland is within its range.

Earlier this month, the regime also threatened to launch ballistic missiles towards the US territory of Guam.

Lieu, a former active duty officer in the US Air Force, recalled his time stationed on the Pacific island.

"What we knew then remains true today: there are no good US military options," he said. "The Kim (Jong-un) regime (of North Korea) possesses nuclear, biological and conventional weapons capable of raining destruction down on millions of civilians and tens of thousands of US service members in South Korea, Japan and Guam."

In the absence of a good military option, the congressman urged the government to channel investments into "game-changing"

technology, such as a layered missile defense system with high-energy lasers that can shoot down North Korea's ICBMs during the initial boost phase.

"The US should harness all the resources of this nation to create a robust missile defense system that can shoot down multiple ICBMs from North Korea," he said. "For the next five years, creating such a defensive shield should be the number one priority of the Pentagon."

The US Ground-Based Midcourse Defense system, which is designed to shoot down an ICBM, will soon have 44 interceptors, according to Lieu. But North Korea is likely to build enough ICBMs in the next decade to overwhelm that system, he warned.

"For over 20 years, we have been staring at the chess board as North Korea carved itself a queen. The smart move now is not to launch a risky offensive, but to put our own new piece on the board that can neutralize theirs," Lieu said. (Yonhap)