Some American Basketball players can get a second passport because their parents (or sometimes grandparents) have different nationalities.
Potential benefits of dual basketball nationality
American players who have dual nationality in basketball can receive either the “Cotonou status,” the “Domestic status,” or the “Bosman status.”
Most professional leagues overseas have an import quota, meaning a maximum number of foreign players per team is allowed. Having dual nationality is a way to work around that.
If a player, for example, has American and Philippine nationalities, he can play in that country as a domestic player. This boosts his chances and sometimes makes him eligible to play for that country’s national team. 
If a player has a passport from a European country, then in addition to the status of the domestic player, he also gets the “Bosman status.” This means that in most other European countries, he will have a higher status than a regular import. More “Bosman players” are generally allowed in a league than true import players. In other words, a passport from a European country gives a player two advantages—that of the country itself, plus that of other European countries.
A Cotonou status is given to players from most African and Caribbean countries. It is similar to the “Bosman status,” but few countries have this rule. In some Middle Eastern countries, an African passport could be an advantage.
Is it worth the hassle?
It may seem that dual basketball nationality has many advantages, but that is not always the case.
A passport alone is not enough. As always, a player must have a solid resume, and in international Basketball, that often means impressive stats at a high level. Having dual nationality does not change the overseas basketball level teams expect from an import or domestic player. If a player has no resume, no stats, and no experience, then dual nationality won’t help much. This is one of the reasons why overseas teams ignore players, even when they hold the right passport. On the other hand, when two excellent players with equally remarkable resumes are competing for the same basketball job openings, the one with a dual basketball nationality might have an advantage.
Elite players who may be good enough to qualify for the national team should definitely consider dual nationality.
All other players need to understand that a good resume gets them jobs. Not a foreign passport.
In addition, getting dual basketball nationality can sometimes be a complicated and lengthy process that could take years, and every player has to ask himself if t is really worth it. Since more and more leagues worldwide are getting rid of the restrictions for import players, it doesn’t matter who has which nationality anymore.