When U.S. President Barack Obama was woken up at 4 a.m. in the morning on Tuesday, he would not have expected the notional threat would come true so soon.

He was told by his staff that North Korea did launch an attack on a South Korean island Yeonpyeong, 120 km west of Seoul. Soon TV images of smoke filled island would have brought the real scene on to the bedrooms of many world leaders.

The attack left two South Korean soldiers died and scores injured with many houses flattened or caught fire in the artillery attack from the North.

South Korea, which is extremely vulnerable with half of its population living within 50 miles of the demilitarized zone, cannot risk retaliation. But unknowingly, the South has walked into the trap laid by the North – resumption of Six-nation talks on its nuclear program, which the South and the U.S. have long been refusing.

Later in the day came the North's explanation through its official KCNA news agency that blamed Seoul to have triggered the firing of shells, prompting it to react. Despite our repeated warnings, South Korea fired dozens of shells... and we've taken strong military action immediately, the statement said.

Caught unguarded, Seoul said it was conducting regular military drills off the west coast but did not aim at the North. We were conducting usual military drills and our test shots were aimed toward the west, not the north, a South Korean military official was quoted as saying by media reports.

The trigger-happy army of the North made it repeatedly clear that it would react militarily whenever the South resumes military drills in the sea. What happened on Tuesday was a knee-jerk reaction from Pyongyang which was cornered to the wall with sanctions. Now that it had shelled the island, not Seoul or the mainland, the message is clear.

The North wants to arm-twist the South into succumbing to the pressure and resume talks. Seoul has repeatedly sought more proof of commitment from Pyongyang to end its nuclear ambitions before resuming the talks. In the past, Pyongyang used these talks to leverage more concessions.

What can Seoul do now? Will it knock at China’s goodwill to intervene? Or call for an emergency meeting of the UN Security Council seeking the ultimate weapon of imposing ship-embargo on its neighbour? Either way, the North stands to lose nothing.

North Korea depends on China for 80 percent of its energy needs, for two-thirds of its trade and investments, besides frequent economic and humanitarian aid which keeps the country going despite sanctions. China remained neutral over the Cheonan incident and assured Seoul that it will not back ‘the offender’, if proved.

The long-drawn Cheonan incident on March 28 when 46 sailors were killed is now eclipsed by a more belligerent attack on Tuesday. Now Beijing will reiterate the same stand seeking more evidence that the South Korean naval guns were, indeed, aimed not at the North but to the west.

Very soon, this may go as another event between the two Koreas which are technically at war still. Unfortunately, Seoul will have to digest the fact that the belligerent North cannot be cowed down easily.

Secondly, North Korea's offer of an olive branch to return to the Six-nation talks on its nuclear program may have to be grudgingly accepted now, in order to engage the enemy than let it go berserk as was the case on Tuesday.