The USA has specific reasons for invading Cuba
Fidel Castro: "We must all remain calm, because a gang, a mafia, has joined the Yankee imperialists ... disgracefully serving the Nazi-fascist government of the United States." This is Fidel Castro's opinion of the European Union, not Cuban dissidents who have settled in Florida. Until recently, the EU has been more loyal to Cuba than the USA, but everything changed in April, after Castro ordered the execution of three ferry hijackers who had tried to make their way to the United States. Dozens of dissidents were arrested as well and then sentenced to long terms in prison. The EU turned its back on Fidel Castro afterward, although it appears Castro was not very upset. On the contrary, Castro got his second wind.
Thousands of people have been participating in meetings and demonstrations to support the Cuban government for last one-and-a-half months. Of course, this is not the first time they have occurred. However, Castro's present zeal reminds everyone of the 1960s, when he had just come to power. Yet, there is a difference. Castro's denunciations of American imperialism used to be "ritual" ones, but now there exists the possibility of military conflict between Cuba and the USA. The Cubans believe that the USA will target Cuba after the successful operation in Iraq – not Iran or North Korea, but Cuba.
Cubans have reasons to believe so. George W. Bush has stressed before that "dictatorships have no place in the Americas." During Bill Clinton's presidency, it seemed that Washington was waiting for Fidel Castro to pass away, thinking that the Cuban regime would collapse afterward on its own. However, George W. Bush's administration is not going to indulge Havana at all. This means that the pressure on Cuba (political, ideological, economic) will continue growing. Repression and arrests against dissidents in Cuba give the American administration a very good opportunity for interfering in the life of the island.
One should not forget that Jeb Bush, the governor of Florida, does not conceal his close ties with representatives of the two-million-strong Cuban Diaspora. It is an open secret that they enjoy a huge influence on everything related to Cuba. Any other governor would be unable to ignore this - but there is hardly a governor who can boast of having a president as a brother.
The dissidents' hatred for Castro's regime is very well known as well. Everyone knows that the passivity of Clinton's administration about Cuba raised anger among the dissidents. The incumbent American president and his team do not suffer from such passivity, though. They would have started dealing with Cuba a lot earlier, if 9/11 attacks and, Afghanistan and Iraqi campaigns had not happened. The dissidents have been asking for a military incursion into Cuba for long time already, and their time may well have come. On the other hand, nothing says that the White House will rush to fulfill all of their requirements. It would be a lot easier to arrange a short victorious war in Cuba than in Iran or North Korea, taking into consideration that the island is located very close to US army and navy bases. Furthermore, the collapse of Fidel Castro's regime would most likely be approved of by the American society: Fidel is a lot worse than Saddam for a lot of Americans.
Of course, it is too early to say that the American army will invade Cuba. However, another propaganda campaign to get rid of the "last dictator" in the Western hemisphere has been launched. However, the dictator doesn’t seem to be depressed by this. A war of nerves can last forever (though one should bear in mind Castro's age, of course), but Cuba is known for its good medical system. And, in the end, the American president might not be the winner of such a war.