Hi, American here. I am fascinated that someone from Sri Lanka (which might as well be Russia, to someone like me) would hear something like "America split the USSR" ... it is the kind of thing I would expect to hear much more in my country than anywhere else... and even then, mainly only from a certain segment of people (the 50% of our population which is conservative/Republican).
Maybe this is not what was being asked, but I thought I would share a bit in the interest of understanding. In the USA there's still a widespread belief, mainly among the older and more conservative people, that the collapse of the Soviet Union was mainly a result of American ideology simply prevailing/"winning" in the battle against pre-Gorbachev Soviet ideology. American ideology was freedom, capitalism, democracy, openness, progress, and "good". Soviet ideology was repression, communism, totalitarianism, secrecy, stagnation, and "evil". These were not separate things, either; if there was communism, then there was all the other bad stuff, too.
Everyone my age and older (40+), when we were kids in school (up to grade 12 / age 18), we learned from history books which were written during the Cold War, so this kind of rhetoric was part of the everyday language. It sounded plausible, and anyone who questioned it was considered a traitor. Many of us also had parents in the military, which was always anticipating that the enemy was going to be the Communists and the Socialists (the words were interchangeable)—the Russians, Chinese, North Vietnamese, North Koreans, Sandinistas, whoever. It was thought they were going to attack us, take away our guns, draft our children to fight in their armies, impose their backward economy on us, take away all our freedoms, impose censorship and corrupt regimes with dictators, imprison or kill all the dissidents, force us to wait in bread lines, take away consumer choices, take away wealth, and so on.
It was the time of the Iron Curtain, so nothing but propaganda ever came from the communist countries, and our own journalists only reported the bad news about those places. As far as we knew, these nightmare scenarios of death and suffering and repression were exactly the kind of thing that had happened in Southeast Asia, and it was happening in Central America, and it is what we heard had happened in the Soviet Union in the days of Stalin and could just as easily be happening today (how could we know?), so we felt we had good reason to be afraid. And...we all were afraid that Russia was going to start a nuclear war.
It was a crazy and terrible time in which to exist, a time of fear and suspicion. But it was also a time when people felt very certain and justified and fortunate to be born in a free country. It was a time when people thought much more (albeit shallowly) about ideology and political philosophy, rather than about celebrity gossip and Transformers movies. In a way, I wish politicians today would speak more about principles and right vs. wrong, but nevertheless, I hope we never go back to those days ... except in music!
Anyway, one popular theory about the end of the USSR is that a communist economy couldn't compete in a global marketplace driven largely by capitalist forces; the pace of everything was just faster in the capitalist/free-market world; everything was growing and technology was advancing, and everyone was successful (well, almost everyone). An adjunct to that theory is that on a fundamental level, humans have certain needs which are better met by free markets, entrepreneurship, and private ownership of property, and that's why even in places where those things are outlawed, there's always a thriving black market based on those things. Even among Democrats (the moderate liberals, approx. 50% of the population), this is a widely held belief.
Of course, the actual reasons things turned out the way they did are much more complicated. It is something that's still being studied and explained, and no one really has all the answers, but I think it is pretty certain, although maybe not well-known in the West, that the reasons are mainly because of things happening inside the USSR, not so much what was going on outside. It was certainly not a case of the U.S. "breaking up the Soviet Union" through economics and ideology. All the Russians didn't wake up one day and say "we like the way the Americans do everything; let's be like them!" Maybe that's what the older and more conservative Americans believe happened, but it doesn't matter...no one cares! These people who think these things have a lot of power right now, but they are running on momentum, and one day they will be old and their views will be irrelevant.
I don't know what the kids' history books say now. I get the impression that the younger generations, they are generally indifferent; Russia is very far away, still, and hardly anyone knows a Russian or anyone who has even traveled there. So to them, it is just a strange place they hear about sometimes, but don't really think about or have an opinion about.
People who pay attention to the news are very wary and skeptical of Putin, but as long as Russia isn't invading any free countries and getting into a war of words against us, it's much more interesting to think about XBox games and silly YouTube videos ... no one thinks for very long about anything too serious...