SEOUL, South Korea -- Addressing her two biggest foreign policy challenges, South Korea's new president, Park Geun-hye, urged Japan on Friday to acknowledge its aggressive past, while pressing North Korea to engage peacefully and abandon its pursuit of nuclear weapons.
"While provocations by the North will be met by stronger counterresponses, the North's willingness to make the right choice and walk the path of change will be answered with more flexible engagement," Ms. Park said in her first national speech after her inauguration on Monday. "I urge the North to hasten efforts to normalize inter-Korean relations and open an era of happiness on the Korean Peninsula together with us."
The South Korean president traditionally addresses the nation on March 1, the anniversary of the 1919 uprising against Japan's colonization of the Korean Peninsula. The event gave Ms. Park an early opportunity to express her thoughts on North Korea and Japan.
South Korea's testy relations with the North have grown much more antagonistic in recent months as the North has tested both a long-range rocket and a nuclear device. And the North, an isolated yet highly militarized country, threatened to conduct further tests if Washington and its allies pushed for more sanctions against it. That complicated the agenda of Ms. Park, South Korea's first female president, even before she started her single five-year term.
During her election campaign, Ms. Park suggested that she would end inter-Korean tensions that were prolonged under the hard-line policies of her predecessor, Lee Myung-bak, during whose tenure the North carried out two nuclear tests and three long-range rocket tests, and was blamed for two military attacks that killed 50 South Koreans in 2010. But she also appealed to her conservative power base by stressing that she would not tolerate the nuclear weapons program and military provocations of the North.
On Friday, American and South Korean forces started their annual Key Resolve and Foal Eagle military exercises, while in the North, the leader, Kim Jong-un, has been visiting military bases, warning of war and calling for "miserable destruction" of the American and South Korean militaries.
"North Korea must realize that nothing will be gained from nuclear development or provocations save for greater isolation and hardship," Ms. Park said. "When North Korea abandons its nuclear ambitions and ceases its provocations, it will be able to become a responsible member of the international community. Only then will the path toward shared development by South and North be opened to us, and only then will the trust-building process on the Korean Peninsula begin in earnest."
Her idea of first building trust as a basis for vigorous economic cooperation with the North is popular among conservative South Koreans. But she has yet to elaborate on how she will reconcile that with the policy of Washington and her predecessor, Mr. Lee, a fellow conservative whose insistence on the North's denuclearization as a precondition of greater economic largess was met only with more provocations from the North.
Her emphasis on both retaliation and "flexible engagement" and the notable absence in her speech of any mention of human rights for North Koreans -- a major concern of South Korean conservatives -- suggested that she was biding her time as leaders in the region were formulating a response to the North's Feb. 12 nuclear test.
"She is telling North Korea not to aggravate the situation any further, while keeping the door open," said Kim Yong-hyun, a North Korea analyst at Dongguk University in Seoul.
Ms. Park was less equivocal on Japan, whose 36-year colonization of Korea from 1910 until its defeat in World War II has overshadowed a thriving economic relationship between the two neighbors.
"The historic dynamic of one party being a perpetrator and the other party a victim will remain unchanged even after a thousand years have passed," Ms. Park said, calling for Japan to have "a correct understanding of history."
"In order for our two nations to heal the wounds of the past as soon as possible and march together toward a future of shared progress," she added, "it is necessary for the Japanese government to change unreservedly and behave in a responsible manner."
Ms. Park came to office after South Korea's relations with Japan deteriorated over a longstanding dispute over a set of islets. In August, Mr. Lee became the first Korean leader to land on the islets, controlled by South Korea and claimed by Japan.
South Korean officials said Mr. Lee's visit was driven partly by Japan's refusal to come to terms with the plight of Korean and other Asian women who, historians say, were forced or lured into working in military-run brothels for Japanese soldiers during World War II.
South Koreans have grown more wary of Japan after Shinzo Abe, a right-wing politician whose nationalist comments had often enraged South Koreans, returned as prime minister after his party's landslide election victory in December. During his campaign, Mr. Abe angered South Koreans by suggesting that he would roll back Japan's past statements of apology to the Asian sex slaves and for its colonial rule.
Last week, his government received a rebuke from Seoul after sending a senior government official to attend a ceremony in Shimane Prefecture in Japan that was held to highlight its territorial claim to the disputed islets.
But Mr. Abe has also tried to reach out to Ms. Park, calling for a better relationship with South Korea. While speaking at the Center for Strategic and International Studies in Washington last week, he said that his grandfather was "best friends" with Ms. Park's father, President Park Chung-hee, the military dictator who ruled South Korea for 18 years until his assassination in 1979.
That remark was met with caution in South Korea, where people are divided over the background of Mr. Park, a former officer in Japan's Imperial Army, under whom South Korea re-established ties with its former colonial master. Mr. Abe's grandfather was Prime Minister Nobusuke Kishi, who served in the wartime Japanese government and was despised by many South Koreans.
This article originally appeared in The New York Times.