The United States
I am united, and
The United States
I am old, like a wine
The United States is over 200 years old.
I am popular now, east to west, but
The United States is quite large for a country, well known, and stretches from its east coast to west coast.
I am misunderstood
It is a commonly held belief that much of the rest of the world dislikes the United States despite many Americans being perfectly decent people.
I am known in several forms/names, but:
There are several names to refer to it: United States, United States of America, America, The States, U.S., U.S.A., U.S. of A.
I am inclusive of many of them:
Historically, the United States was a very inclusive place. Additionally, many of the previous names are well accepted.
I am given a day, but
I am good for a life time
The United States revolution barely established the United States as a country (hence "given a day" to refer to a short amount of time). But, it was later established that the United States is definetly a country (hence "good for a life time")
I am present now, and
I am alive now
The United States definitely exists and is "alive" in a metaphorical sense.
I am here to help you so that,
I am to be attained by you
There is a common narrative in the United States about it being a "world policeman" who is there to fix other parts of the world. If we take the words "United States" to be a representation of democracy (not to imply other democracies don't exist -- but, the United States was arguably the first and was a model for many others), then the "help" offered by the United States should help establish democracy (hence it can be "attained") in other parts of the world.