2010 will be remembered as the year tensions on the Korean peninsula soared to their highest level since the war there in the early 1950s. As the year ends, the two Koreas find themselves engaged in an escalating war of words, after two significant, deadly, clashes.
The scenes of homes ablaze on a South Korean island in late November - from a North Korean artillery attack - stunned and angered this country.
South Korea later staged a live-fire artillery exercises, prompting a renewed warning from Pyongyang.
"The political situation on the Korean peninsula is reaching an uncontrollable extreme level by the frantic provocations of the puppet group. No one can predict what this situation will turn into," said an announcer on North Korean TV.
Amid the saber rattling, South Korea, Japan and the United States resolved to have their soldiers and diplomats work more closely together.
The U.S. military conducted war games with each ally to send a message of deterrence to North Korea.
And the three countries' top envoys met in early December to demonstrate a united front, express concern about North Korea's nuclear weapons programs and send a signal to Beijing.
South Korean Foreign Minister Kim Sung-Hwan had this to say to Pyongyang's lone significant ally. "We would like China to play a more important role. And regarding this, we will consult closely with the United States and Japan," he said.
North Korea's shelling of Yeonpyeong island came nearly seven months after the sinking of a South Korean navy ship that killed 46 sailors. An international investigation blamed a North Korean torpedo, but Pyongyang denies responsibility.
Some regional security experts suspect the two attacks were meant to bolster the image of North Korea's youngest four-star general, Kim Jong Un, who has no military background. But he is the son of absolute leader Kim Jong Il, and is expected to succeed his father, and his grandfather, in ruling the country.
Father and son made their first prominent joint appearance for the world's cameras at a military parade in Pyongyang in October.
As 2010 drew to a close, South Korea's leaders promised swift and substantial retaliation if North Korea strikes again. Most South Koreans are growing increasingly anxious, unsure just what might come from across the border in 2011.