Next week marks the 40th anniversary of one of the most momentous and unexpected events of the 20th century -- President Richard M. Nixon's visit to Communist China of Chairman Mao Tse-Tung.

The most vociferous critics of Nixon would have to acknowledge that the path towards normalizing relations with Beijing represented one of the greatest political achievements in U.S. history.

However, the historic trip was indeed strange and controversial.

For one thing, Nixon established his early political career during the red-baiting period after World War II as an arch opponent of Communism, aligning himself with the activities of Senator Joseph McCarthy and others.

But by Nixon's first term as president (almost two decades after the Communist witch-hunt), he had decided that it was crucial to U.S. foreign policy to commence some form of rapprochement with the Chinese – perhaps to form a bulwark against the Soviet Union.

Nixon's National Security Adviser Henry Kissinger played a key role in the intrigue behind the China journey by making secret diplomatic overtures to the Chinese for at least three years before the visit. Reportedly, the White House used ally Pakistan as a conduit to reach the highest officials in Beijing.

Jamie Chandler, professor of political science at Hunter College in New York City, explained that Nixon's trip was the culmination of years of complex “Ping Pong” diplomacy.

“Nixon had expressed an interest in changing relations with 'The Sleeping Dragon' even before his presidency,” he said.

“But the Chinese were cautious. Rapprochement talks began through third-party channels in 1969, and didn't become sustained until 1971 -- due to the U.S.'s 1970 invasion of Cambodia and its diplomatic recognition of Taiwan.”

The president and his advisers met with senior Chinese government figures, particularly with Premier Chou En-Lai, and at least one parley with Mao himself.

A photograph of the former anti-Communist zealot Nixon and the leader of China smiling and shaking hands became an extraordinary, iconic image from the week-long trip. Nixon himself called his visit the week that changed the world.

At the conclusion of the visit, Washington and Beijing released the Shanghai Communiqué, which stated the two nations' foreign policy stances and served as a kind of framework for future cooperation and relations between the erstwhile intransigent enemies.

Nixon, a polarizing figure in a U.S. wracked by campus protests, opposition to the Vietnam War and racial conflicts, nonetheless received almost universally favorable coverage for his visit, which was heavily covered by television and print journalism.

Among the most important strategic results from Nixon's visit related to U.S. relations with Taiwan. By 1979, under President Jimmy Carter, Washington severed formal relations with Taiwan and formed full diplomatic ties with Mainland China.

Indeed, as Chandler indicated, China based normalization of relations on the U.S. agreeing to disavow Taiwanese independence and committing to troop withdrawals from the island and Vietnam, once the war ended.

Mao, who was in poor health, when he greeted Nixon, would die within four years of the historic visit. Nixon himself would be out of office two years later.

The Chairman could not possibly have foreseen how much his vast country would radically change and evolve over the next four decades.

In 1972, the Chinese economy was a shadow of the modern powerhouse it would blossom into some day.

“[During the time of Nixon's trip] China's GDP was $112 billion compared to its current $5 trillion, and the country was in the throes of the aftermath of Mao's failed Cultural Revolution,” said Chandler.

“Anti-capitalist thinking was rampant. State policies exiled privileged urban youths to rural farming villages, closed universities, and ruined the country's infrastructure.”

Chandler noted that Nixon's bold step yielded some immediate dividends for both the U.S. and China.

“The mission gave Nixon a major diplomatic victory, boosted his approval ratings, and transformed [global] perceptions of China,” he said.

“It [also] compelled the Soviet Union to sign the 1972 SALT I Arms Control Treaty; and also opened media access to the long-isolated country, giving the U.S. public a first-hand look at life behind the Great Wall.”

However, the visit did not immediately spark trade between the U.S. and China.

“The meeting didn't hinge on bilateral trade talks, so very little economic benefits followed,” Chandler stated.

“It took several years to build trade relations, because the U.S. didn't officially recognize China until the passage of the Taiwan Relations Act in 1979, nor was China ready for more robust trade until after the commencement of its economic reforms in 1978.”

Indeed, it has taken American products and services decades to penetrate China's vast market and it will probably take many more to reap peak returns, Chandler added.

Nixon's surprising trip to China also had a dramatic impact on Russia and India.

“The trip was one of many components that fueled the Sino-Soviet split through 1989, and also compelled Russia and the U.S. to move more quickly toward an arms reduction treaty,” Chandler said.

After the trip, Nixon made efforts to improve Soviet relations including having a marathon meeting with Russian leader Leonid Brezhnev in 1973, and holding a Moscow summit in 1974.

“But the Watergate scandal and Nixon's imminent resignation [in 1974] limited expectations on both sides,” Chandler added.

As for Indo-American relations, they were already tenuous, since the U.S. sided with Pakistan during the Indo-Pakistani War of 1971 and Kissinger had been carrying out a “tilt” policy away from India because of it close relations with Moscow, since 1969.

Nixon, who has a highly troubled legacy in the U.S. and Europe, remains an admired figure in China.

“The Chinese leaders and people alike regard Nixon as a great friend, respecting him for him for his fortitude, intelligence and strong personality,” Chandler stated.

“They saw his 1994 death as a great loss.”

Minxin Pei, professor of government at Claremont McKenna College in Claremont, Calif., wrote that Nixon's gambit reshaped “Eurasia’s geopolitical balance and put the Soviet Union on the defensive. But the long-term outcome of America’s rapprochement with China became visible only recently, with the economic integration of the People’s Republic into the world economy.”

Pei proposed that in the absence of Nixon, China’s self-imposed isolation would likely have continued.

“Deng Xiaoping’s reform and opening of China to the world would have been far more difficult,” Pei added.

“Global reintegration has turned China into an economic powerhouse. It is the world’s largest exporter in volume terms, and is the world’s second-largest economy. China’s presence is felt around the world, from mines in Africa to Apple stores in the U.S.”

Indeed, Nixon changed the world forever.