Schengen is in reality nothing more than a loose agreement between some European "states" which means increased freedoms for their citizens to move freely and without passport checks still exist. During the last few years we have many examples on how arbitrary this agreement is.
The excuses could be and has been many for the states to break or improvise with Schengen, but no excuse has been particularly reasonable. Too often, it has been an expression of a power struggle at the expense of the citizens.
Truthfully, Schengen is a half hearted attempt from the beginning to bring the people of europe closer and to create a sense of citizenship, atleast it would appear so on paper.
Here is why:
- Schengen don't include all EU states and therefore not all citizens.
- The Schengen area don't have a common border authority.
- Some EU states want to limit the freedom of movement all together for all or some citizens.