U.S. Defense Secretary Ash Carter cautioned against linking the current tensions over North Korea's planned long-range rocket launch to his previous calls for a preemptive strike on the communist nation a decade ago.

In 2006, Carter made the case for a preemptive strike in an article contributed to the Washington Post, just a couple of weeks before the North defied international warnings and test-fired a Taepodong-2 long-range missile on the July 4 Independence Day holiday.

Carter, then a Harvard University professor, jointly wrote the article with former Defense Secretary William Perry, who was then a Stanford University professor, arguing that a preemptive strike is risky but the risk of continued inaction in the face of the North's race to threaten the U.S. would be greater.

On Tuesday, Carter was asked if he still has such a view. "Well, that was a different circumstance then. It was a test launch missile, and our policy was that we were not to tolerate it.

And we were trying to figure out how to not tolerate it. So that was then, and now is now," Carter said during an event at the Economic Club of Washington.

Carter said that the North's nuclear and missile programs are serious concerns, as are the size of the North's force positioned along the Demilitarized Zone separating the two Koreas, as well as the size of its special forces.

"And I've just got to remind you, we're on the Korean peninsula. We will win, no question about it. But it is a very, very savage and intense war, and so it's not an area where you want deterrence to fail. But deterrence has to be incredibly strong there and every day we need to do it," he said.

Asked about the North's claims of a successful hydrogen bomb test, Carter said he doesn't think the North was as successful as it claimed. Still, however, he said he takes no consolation from that because of what he calls a "really serious combination" of the North's nuclear and missile programs as well as its "odd demeanor."

The already-high tensions on the Korean Peninsula in the wake of the North's Jan. 6 nuclear test rose even higher this week as Pyongyang unveiled its plan to carry out a banned long-range rocket launch in violation of U.N. resolutions.

North Korea says its rocket launches are aimed at putting satellites into orbit, claiming it has the right to the peaceful use of space. But Pyongyang is banned from such launches under U.N.

Security Council resolutions as it has been accused of using them as a cover for testing intercontinental ballistic missiles.

Experts say long-range rockets and ICBMs are basically the same with differences only in payloads.

South Korea urged North Korea to call off the planned launch, warning that Pyongyang will "pay a harsh price" if it goes ahead with the plan. The U.S. also denounced the North's move, saying it shows the need for "real consequences" for such provocative acts.

Even China, which has provided the North with economic aid and diplomatic protection, expressed "serious concern," saying that Pyongyang's right to the peaceful use of space is now restricted by U.N. Security Council resolutions, and urged the North to exercise restraint. (Yonhap)