Puerto Rico has been an American territory since the Treaty of Paris in 1899 (as a direct result of the Spanish-American War). And it's 3.5 million inhabitants have been American citizens since 1917 (when the Jones-Shafroth Act gave citizenship to all those born after 1898).
But while they have been American citizens for over 100 years now, they still do not have the same rights as other American citizens. They have no voting representation in Congress, and they cannot vote for the U.S. president. They have no voice in how their own federal government makes decisions that affect them.
That is unconscionable. It is time to give them the rights they so richly deserve. The U.S. government should either make Puerto Rico a state, or cut them loose to form their own country (with that decision being made by the citizens of that island in a fair vote). I believe they would choose statehood -- and I believe most Americans would happily welcome them into the roll of states.
The chart below shows American attitudes toward making Puerto Rico a state. In the last year, there has been movement toward statehood -- with 47% now favoring that, and only 34% opposing it. Last year, it was 40% favoring and 39% opposed.
The most recent Rasmussen Poll was done between January 18th and 21st of a random national sample of 1,000 likely voters, with a margin of error of 3 points.