Japan is considering the development new weapons systems to prepare a first-strike against North Korea's nuclear program, according to Japanese lawmakers.

"It is time we acquired the capability," said Hiroshi Imazu, a legislator who helps set security policy for Prime Minister Shinzo Abe's political party, according to Reuters. "I don't know whether that would be with ballistic missiles, cruise missiles or even the F-35 [fighter bomber], but without a deterrence North Korea will see us as weak."

Such an armament would represent the boldest expansion of Japanese offensive capabilities since World War II, in a country that has created constitutional restrictions on military development. But North Korea's increasing pattern of aggression in the region has neighbors looking for new ways to counteract the dictatorship.

U.S. military aircraft delivered the first components of a missile defense system to South Korea on Tuesday, two days after North Korea launched four missiles in the direction of Japanese territorial waters in apparent protest of U.S. and South Korean military exercises. Secretary of State Rex Tillerson is traveling to the region next week to discuss plans for cracking down on the regime, which may include military options.

"We are very concerned with the escalation of North Korea's actions, the continuous testing and augmenting of its weapons program is of great concern and it's getting to the point where we do need to look at other alternatives and that's part of what this trip is about, that we're going to talk to our allies and partners in the region to try to generate a new approach to North Korea," acting State Department spokesman Mark Toner told reporters Tuesday.

China, long an enabler of the North Korean regime, recently tightened implementation of economic sanctions imposed last year by the United Nations Security Council.

"[China], styling itself a big power, is dancing to the tune of the U.S. while defending its mean behavior with such excuses that it was meant not to have a negative impact on the living of the people in the DPRK but to check its nuclear program," North Korean state-run media replied in a mocking column.

But China has registered vehement opposition to the deployment of the missile defense system to South Korea, saying the system would undermine strategic balance, and invoked Japan's imperialism during the Second World War.

"Due to historical reasons, moves taken by Japan in the fields of military and security have always been followed closely by its Asian neighbors and the international community," Ren Guoqiang, spokesman for China's Ministry of National Defense, said in February. "We urge Japan to take history as a mirror, observe its commitment to the path of peaceful development, and do more to improve mutual trust with its neighbors and contribute more to regional peace and stability."

Japanese lawmakers may be growing immune to such taunt. "China has missiles that can hit Japan, so any complaints it may have are not likely to garner much sympathy in the international community," Reuters quoted Itsunori Onodera, another member of the ruling party working on defense issues, as saying.