The idea of having a universal language, especially if it is arbitrarily chosen or worse, forced, would be next to useless. English would be just one of many bad choices. English uses so many rules with exceptions that anything past the basics would be a barrier to those that need to use the language if it was chosen as a universal language. As English speakers who learned it at our mothers knee, we find the language easy to use (for the most part; you don't have to look very far to find examples of bad English). For a language to be truely universal it must be as natural as possible for any and all speakers or else those that don't master it to a high degree already suffer a disadvantage to those that do master it. As a second language it is VERY difficult to master.
There isn't a national language out there that would permit most people to learn it like a native. The deadlock over which language would get ugly indeed.
However, an AUXILIARY language, intended to bridge the gap between cultures by providing an easily learnt method of communication would be the answer. It would open the EU and indeed, the world up to far more in the way of understanding.
Esperanto is making headway in becoming an AUXILIARY language, yet people reject it out of hand because they all fear the loss of their tongue and a single language spoken by all, which of course is exactly what Esperanto is trying NOT to do.
As a common SECOND language you and you and you have no need to sink years into study of a language that you will most likely NEVER fully assimilate like a native. The choice would be yours. With Esperanto you can be comfortable talking to your neighbour in your native tongue and just as comfortable talking to Ming Lu across the waves on an equal footing in this easily learnt language. It's like a neutral handshake, because each participant invested an equal amount of effort to learn this easy language. (16 gramatical rules... NO exceptions!)
Believe it or not, Esperanto represents the best chance for the survival of the multitude of dying languages since it's purpose is to forestall the monopoly of any one National tongue to the disadvantage of another.
So will it some day become universal (which by the way doesn't mean that EVERYBODY in the world speaks it, just those that want it / need it)?
Well, the $600 million+ USD spent yearly on translation services at the UN (six official languages) and a similar amount in the EU says, sooner or later something is going to change, and this is the cheapest and most effective, proven alternative.
Further, if you don't think Esperanto is making headway, check this.
In a recent reprint of the Unua Libro (first book), editor Gene Keyes said that when he first started the project in 2000, he did a search for Esperanto on Google and it yielded over 1 million hits. At the completion of his task in February of 2007, the same search yielded over 34 million hits. Out of curiosity, after I had read that I did the same search and it yielded over 39.2 million hits. That's up over 5 million in two months. So it's growing. Slowly (or maybe not so slowly!)
Obviously not everyone will find a use for it, and that's fine. However for those that take the time and bother to search out the other users, it's worth it. Of course searching out other uses gets easier with each passing day.
Personally I have friends all over the world. Friends I wouldn't have had with out Esperanto.
Some have the opinion that the language is Impractical and awkward.
The two million plus (as of 1995) people that use it says it's not Impractical. Two million was considered the functionally fluent level (IE: able to get by in the necessary elements when travelling) in 1995. Since 1995 the Internet has grown by leaps and bounds, and Esperanto right along with it.
As for awkward, well I don't agree, but then anything that you start might be considered awkward until you get the practice in that you need.
Wikipedia hosts more than 250 different languages. Esperanto ranks 22nd in the most numerous articles category.
More than these languages to name a few.
23 Slovak
24 Danish
25 Indonesian
http://meta.wikimedia.org/wiki/List_of_Wikipedias
NOBODY has to give up their mother tongue, nor should they.
Esperanto as an auxiliary language however would be wonderful.
I encourage everybody to research and draw their own conclusions.
Ĝis!