U.S.?China ties, note some observers, are evolving into one of the most important international relationships of the 21st century.  But the differences between these two powerful nations and uncertainties over China?s future are putting a strain on that relationship.

Many observers note the key purpose of President Hu Jintao?s first visit to Washington is maintaining already close U.S. ties.  They say top-level meetings have been a key part of the relationship ever since the Sino-American rapprochement initiated by former President Richard Nixon, more than three decades ago.

James Lilley of the American Enterprise Institute, served as U.S. ambassador to the People?s Republic of China from 1989 to 1991. He argues, ?Summitry plays a key part in the relationship and that?s been the case since the very beginning in 1971 with Henry Kissinger and then Nixon and Kissinger in 1972.  You need to have a consistent summitry at the highest level so these men can get to know each other, get to meet the staffs, talk with them and go through the protocols of leadership.?

Stakeholders or Competitors?

U.S. Deputy Secretary of State Robert Zoellick has been credited with coining the term ?stakeholders in the international community? to describe the U.S.-China relationship, a change from the term, ?strategic competitors? initially used by the Bush administration.  The shift, note many analysts, is meant to acknowledge the progress of Beijing?s reforms, while leaving room for those who continue to see China as a rising challenge.

High on the agenda are expected to be security issues such as Iran, North Korea and Taiwan.  Many China-watchers underscore that Mr. Hu?s visit is an opportunity for him to allay concerns among U.S. officials about China?s ?soft power.?  Beijing?s extensive energy arrangements with Iran and Sudan, for example, are viewed as a key obstacle to Washington?s calls for U.N. action against Iran?s nuclear program and Sudan?s human rights violations in Darfur.

Elizabeth Economy, Director for Asia Studies at the Council on Foreign Relations in New York, says America recognizes China as an emerging economic power, but wants to know whether it desires to be an ally of the West. 

"We understand the need for China to seek out resources to continue to develop its economy," says Economy. "But what does it mean when they start to develop military relationships with countries in Latin America, Africa or Southeast Asia?  When it moves beyond the economy, we begin to wonder: What are China?s ultimate aims?"

President Hu and President Bush will also likely focus on trade issues, which center on intellectual property rights, Beijing?s artificially low currency rate and access to China?s market.  According to U.S. officials, all of this is causing a ballooning U.S. trade deficit with China, which last year exceeded $200 billion and prompted Congressional calls for tariffs on Chinese goods. 

In advance of President Hu?s visit, a group of 100 Chinese business executives -- headed by Wu Yi, China?s vice-premier -- recently traveled to 13 American states hard hit by the outsourcing of jobs to China.  The trip resulted in multi-billion-dollar-orders for U.S. aircraft, auto parts, computer software, telecommunication equipment, grain and cotton. 

China?s Lopsided Reforms

But many analysts contend that solving key trade issues between the two countries will be difficult, primarily because of what economists call ?structural distortions? of China?s economy, such as over-reliance on foreign markets.  About 80 percent of China?s gross domestic product comes from foreign trade.  But adjusting China?s currency value, a key issue for the United States, would incur huge losses for China.

Elizabeth Economy of the Council on Foreign Relations notes other problems associated with China?s economic transition.  She says Beijing?s investment-driven growth strategy is generating tremendous social strains:  corruption, environmental degradation, a poor public health system and an enormous economic underclass.

"There are a lot of domestic problems in China that could cause a serious disruption to China?s continued economic growth," says Economy. "You can look at the environment, banking system, social unrest. This is a country that last year had 87,000 protests. It is very difficult for people in China to figure out exactly how to address these issues."

Charles Horner is a political scientist at the Hudson Institute in Washington adds, "They have to figure out how to keep this program of rapid economic growth on track and at the same time deal with the problems it has created for them. Many of these problems have international implications and are linked to the relationship with the United States. That?s why these questions about trade, energy and evaluation of the currency are so prominent.  They are not abstractions; they have a natural practical significance to what?s going on in China right now." 

But Charles Horner also notes that China?s continued transformation could help its leaders see themselves as strong ?stakeholders in the international community?. Most analysts agree this is key to furthering China?s relations with the United States.  And some argue that closer political ties between the two nations could make a crucial contribution to international relations in the 21st century.

This story was first broadcast on the English news program,VOA News Now. For other Focus reports click here.