Here's my take on this...
The international banking cartels are focusing on ransacking the few remaining capitalist countries in the world, and aren't making a lot of loans to Communist nations anymore. Since the fall of the USSR, their aide (in the form of money, military support, fuel, and agricultural supplies) has dried up and Russia isn't stepping up to fill the void. The European and Canadian investers that were allowed into Cuba aren't throwing much money there anymore either, because they have their own issues.
The Castro dynasty is nearing it's end. The tourism industry is nearly dead in Cuba, due to the lack of infrastructure and the massive decline in international air travel these days. The only other industry in Cuba worth any note is agriculture (tobacco and sugar cane) ad those are both in trouble due to anti-smoking laws worldwide, and th egrowing use of GMO corn for making high fructose corn sugar as a substitute for cane sugar, plus they can't even get fertilizer or diesel for their tractors.
The Cuban government sees the writing on the wall. They know that once the global banking cartels finish raping and pillaging the "free world", they will begin their "final campaign" to wipe out all the third world nations and return them to total serfdom. The boys in Havana know that their people are strong willed, nearly at the end of their rope, and perfectly willing and able to pull off a "new revolution", and they don't want to take any chances.
So they're going to use this ruse to completely disarm the populace, so when the people have finally had enough, they can't rebel. I see this grab for guns in Cuba as the last desperate act of a regime who knows it's day's are numbered.
It's sad, really.
Pray for our brothers and sisters in Cuba. They've had to live under a repressive regime for nearly half a century. Hopefully, they wil take back their nation soon, before the "blue-helmets" roll in and just start eradicating everyone...