"DROP TABLE cannot be used to drop a table that is referenced by a FOREIGN KEY constraint. The referencing FOREIGN KEY constraint or the referencing table must first be dropped. If both the referencing table and the table that holds the primary key are being dropped in the same DROP TABLE statement, the referencing table must be listed first."
So sayeth books online.
You could write your script to peruse the system tables and drop the constraints first...
If it's not practically useful, then it's practically useless.