A flotilla of 20 American and South Korean Navy ships churned the waters off South Korea’s east coast Sunday on the first of four days of military exercises in a show of force that North Korea promises to answer with a “powerful nuclear deterrence.”

The rhetoric from North Korea, however, appears to most observers as just that – words that suggest a long-range determination to stick to its nuclear program while avoiding an immediate military confrontation.

“This is just a verbal threat,” says Choi Jin-wook, senior fellow on North Korean issues at the Korea Institute of National Unification, a Seoul-based think tank. “It’s just a bluff.”

What the war games entail

The military exercises, led by the 98,000-ton Nimitz class aircraft carrier, come in the aftermath of the sinking of the South Korean Navy vessel, the Cheonan – in the Yellow Sea, on the opposite side of the Korean peninsula – in March. The carrier has 80 war planes taking off from its decks while more than 100 other planes are flying from the major United States air base at Osan, about 30 miles South of Seoul. The exercises, called “Invincible Spirit,” also include destroyers with Aegis-class counter-missile systems – the latest technology for fending off missiles of the sort that North Korea has tested over the years.

The emphasis is on antisubmarine warfare with ships and planes looking for dummy targets similar to the midget submarine that an investigation, led by South Korea and including experts from the US, Britain, Australia, and Sweden, concluded had fired the torpedo that split the Cheonan in two. North Korea continues to deny any role in the attack, in which 46 sailors were killed, but has said it wants to talk about it with investigators.

What does North Korea want?

After the war games are done on Wednesday, all sides are expected to turn to the possibility of negotiations on North Korea’s nuclear program.

“[The North Koreans] are very distressed by these exercises,” says Mr. Choi, “but they’ve already said they’re going to resume six-party talks [with US, China, Japan, Russia, and South Korea]. That’s what they want. They do not want war.”

But the North Koreans have made clear that they are not going to go along with demands to get rid of their nuclear program even if they return to the table. North Korea has called for “denuclearization” of the entire Korean peninsula – a term that is likely to include banning all nuclear arms from US ships in the Pacific and even banning nuclear-powered vessels such as the George Washington.

And no one rules out the possibility of more North Korean missile and nuclear tests.

North Korea has conducted two underground explosions of nuclear devices, in October 2006 and again in May of last year, and also has tested a long-range missile capable theoretically of carrying warheads as far as Alaska, Hawaii, or even the west coast of the US.

Choi predicts “they will try to conduct a nuclear test or a missile test” but notes the North faces severe internal problems. North Korea's reclusive leader Kim Jong-il, suffering from a variety of illnesses, is attempting to put on an appearance of strength while preparing for his third son, Kim Jong-eun, to take over when he leaves the scene.

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