The first option is to effectively enforce a new set of toughened sanctions imposed following Pyongyang's fourth nuclear detonation to curb the North's adventurism.
The second is to consider accepting overtures to negotiate suggested by North Korean foreign affairs chief Ri Su-young on his U.N. visit to induce a least-destructive, if any, implosion in the North over a longer period of time.
However, this two-way approach has, in my view, slim chances of altering the perilous course of brinkmanship by the North.
North Korea is heavily steeped in the mistaken belief that pursuing nuclear armament while continuing a peace offensive brings Pyongyang the room to maneuver for survival as it has done successfully so far.
The proposed actions to rid the North of its nuclear arsenal still let Pyongyang keep the initiative on nuclear and missile issues.
To bring enduring changes to North Korea's misbehavior, South Korea and the international community should take back the reins and force Pyongyang to take the path of denuclearization.
Here is my proposal: The international community seeks to intercept missiles test-fired by North Korea in violation of U.N. Security Council resolutions.
Once missiles fly out of North Korean territorial waters into airspace over international waters, they should be intercepted with missiles from the trilateral coalition of South Korea, the United States and Japan under a new UNSC resolution granting authorization for such action to the coalition.
Under well-established international law, obligations under the U.N. Charter, including those in the Security Council's resolution invoking Chapter VII, prevail over any other obligations for member states.
(The U.N. Charter stipulates non-military and military enforcement actions in Chapter VII.)
This means that a shift to the interception strategy will break no international laws, and North Korea will not be entitled to complain of its missiles being brought down by a U.N.-approved measure if a relevant Security Council resolution is adopted appropriately.
Shooting down missiles in midair over high waters precludes North Korea from obtaining necessary data on developing technology regarding reentry of long-range missiles and nuclear miniaturization, hence an effective freeze of its missile tests.
With the effort to convince China of the benefits of the enforced freeze, this proactive strategy will shatter Pyongyang's myth of its brinkmanship's continued tolerance and draw a dejected Pyongyang out to the negotiating table for a nuclear-free Korean Peninsula.
Now is the time for South Korea to take a proactive bolder move to stop North Korea's nuclear escapade.
Kim Keon-yeon is a Seoul National University graduate preparing for the Korea National Diplomatic Academy exam.