U.S. President Barack Obama on Sunday headed for his first visit to Vietnam, looking forward to transform an old enemy into a new partner to help counter China’s growing assertiveness in the region, following four decades of the Vietnam War. This visit is expected to deepen defense and economic ties with the country’s communist government while also prodding them on human rights, aides say.

Obama’s Vietnam visit comes just days after Chinese fighter jets carried out what the Pentagon described as an “unsafe” intercept of a U.S. military reconnaissance plane in the South China Sea. The latter’s visit marks the third by a U.S. president to Vietnam since diplomatic relations were restored in 1995.

“What we want to demonstrate with this visit is a significant upgrade in the relationship between the United States and Vietnam … even as we have areas of difference,” said Ben Rhodes, Obama’s deputy national security adviser.

Washington wants Vietnam to open up more on the economic front and also move closer militarily, including increased port visits by U.S. warships, possibly with access to the strategic harbor at Cam Ranh Bay, U.S. officials say.

Despite the visit, there will be reminders of the past. For instance, Obama won’t be able to avoid displayed images of the late Vietnamese leader Ho Chi Minh, honored by many of his compatriots but commonly unloved in the United States during the war. The conflict involving U.S. combat forces was estimated to have killed hundreds of thousands of Vietnamese and 58,000 American troops.

Obama plans to meet dissidents amid U.S. concerns about the government’s heavy-handedness toward opponents. Hanoi released a Catholic priest, one of its longest-serving prisoners, on Friday, in a possible gesture ahead of Obama’s visit.