The idea was that there would be one currency and a federal government that would act in much the same way as does the federal government in the US. They began, very sensibly, with trade agreements and slowly expanded.

Over the ensuing years, the national leaders of Europe steadily pushed forward toward the major goal of a unified Europe under a federal leadership. They reached this point with the Maastricht Treaty in 1992.

My personal belief was that the concept would not succeed over the long haul. Whilst trade agreements can be very beneficial for European countries, the idea that Europe can be unified under a single government and a single currency was, in my opinion, doomed to failure.

The United States was created primarily for the defence of the thirteen American colonies, so that a minimalist central government could protect all the colonies equally. Of course, as soon as the idea was ratified, some political leaders began to try to expand that centralised power. The US federal government then grew, a bit at a time, and eventually became dominant over the states.