Story highlights Fidel Castro was a throwback to a bygone era, writes Nic Robertson

Relations between US and Cuba improving

Raul Castro has said he will step down in 2018

(CNN) Fidel Castro's death is the end of an era. He has gone not with a bang, as he arrived, nor with a whimper, but a simple fading away. Laid low by serious illness, his iron grip on the island nation had loosened over the past decade, with full power passing to his brother Raul in 2008.

Castro's communist impulses were imprisoned by his increasing infirmity. In his failing years, he witnessed much of what he stood for slip away. Diplomatic relations with the US -- that 50 years ago had the world on the brink of nuclear war -- are on the mend. Whether he backed his brother in this detente is unclear; what is clear is that a quarter of a century after the collapse of their principal sponsor -- the Soviet Union -- neither of the brothers could stand in the way of their people's wishes any longer.

Cuban President Fidel Castro waves a flag during a visit on January 27, 2001 to the Havana neighborhood of San Jose de las Lajas.

Over the decades, plans were hatched to remove Castro by force if needed -- the CIA reputedly plotted to put explosives in one of the Cuban leader's favorite cigars. Despite the machinations, he survived to be a thorn in the side of every US administration.

Obama's legacy

A throwback to a bygone era of Communism that most of the world had forgotten, Cuba was less than 100 miles from the home of capitalism, America. This situation could not last.

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