But there are also signs that China and Myanmar, so close for two decades, are having differences.
In Igor I. Sechin, Rosneft has a chief executive of proven energy, who as Mr. Putin's closest aide for two decades enjoys the president's strong backing.
Gabe Pascarella, an Atlanta businessman who testified at the trial, said he was surprised to hear that Mr. Campbell, a close associate for two decades, had undergone substance abuse treatment.
After an arduous trip he took up residence as ambassador there in August 1806, being briefed by Baron von Vincent, and Engelbert von Floret whom he would retain as a close adviser for two decades.
He is contributing his time to an effort to restore the Miami Marine Stadium, a 1964 structure that has been closed for almost two decades, as the centerpiece of a waterfront park.
Less than 70 kilometers, or 45 miles, apart but separated by a border that has been closed for nearly two decades, cheese makers in Gyumri and Kars, along with colleagues in the nearby Georgian town of Ninotsminda, produce and market a "Caucasian cheese," invented by Mr. Mkrtchyan in 2008 to foster cross-border cooperation.
The case of Russia is particularly instructive: Closed off for seven decades, the nation's leaders opened the doors to new ideas and capital in the aftermath of the Cold War.
Egypt was Moscow's closest Arab ally for two decades, starting in the 1950s.
And yet, Beirut has a park the size of Central Park, located in the middle of the city that's been closed off to the public for two decades for no real reason at all -- other than to prevent social cohesion that could perhaps lead to a questioning of the government.
I replied, Certainly not, I have kept this love note in my wallet, close to my heart for two decades.
