What is the deeper meaning or explanation of this quote?
A true revolutionary is like a true patriot. He loves his cause, and he knows he's right because he represents the people. A patriot goes to war and risks his life because he loves his country. A true revolutionary goes to war and risks his life because he loves the oppressed. And I think Che is right. By definition. We've seen a lot of 'strong men' posing as revolutionaries, but they only represented themselves and their friends. That's not a revolutionary, that's a tyrant.
`Love`s The Only Engine Of Survival` is a line from a Leonard Cohen lyric - and the man had a strong strong political sense too.
I think it's self-explanatory. Revolutionaries have generally been motivated by wanting better conditions for the people. That was true in Russia when the majority of the people were starving, and a few rich people were living luxuriously, and it was true in Cuba, where the workers were oppressed by the elite. Fidel Castro was beloved by the people of Cuba because he genuinely wanted to benefit them, not to enrich himself. He never slept in the same place two night running (because of US attempts to assassinate him), and he was constantly looking for ways to improve the nutrition of the Cuban people.