I have set up 3 tables that have foreign keys and primary keys. I want to delete these 3 tables but I cannot delete any of them because:
mysql> DROP TABLE POST, TOPIC, USER;
ERROR 1217 (23000): Cannot delete or update a parent row: a foreign key constraint fails

I get that certain tables cant be deleted because other tables have keys from that table, but if I try to delete all 3 tables in the equation then why do I still run into the same problem? How can I go about deleting these 3 tables.

mysql> DESCRIBE USER;
+------------+-------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+------------+-------------+------+-----+---------+-------+
| U_ID | varchar(16) | NO | PRI | NULL | |
| U_PASSWORD | varchar(16) | YES | | NULL | |
| T_ID | int(11) | NO | MUL | NULL | |
+------------+-------------+------+-----+---------+-------+
3 rows in set (0.02 sec)

mysql> DESCRIBE TOPIC;
+---------+-------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+---------+-------------+------+-----+---------+-------+
| T_ID | int(11) | NO | PRI | NULL | |
| POST_ID | int(11) | YES | MUL | NULL | |
| T_TEXT | text | YES | | NULL | |
| U_ID | varchar(16) | NO | MUL | NULL | |
+---------+-------------+------+-----+---------+-------+
4 rows in set (0.01 sec)

mysql> DESCRIBE POST;
+-----------------+-------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+-----------------+-------------+------+-----+---------+-------+
| POST_ID | int(11) | NO | PRI | NULL | |
| U_ID | varchar(16) | NO | | NULL | |
| POST_MESSAGE | text | YES | | NULL | |
| POST_SUBJECT | varchar(35) | YES | | NULL | |
| T_ID | int(11) | NO | | NULL | |
| POST_COMESAFTER | int(11) | YES | | NULL | |
+-----------------+-------------+------+-----+---------+-------+

ERD: http://img14.imageshack.us/img14/8690/41633351.gif
Youll see a PROFILE tables exists. It was there but it is the only one that would drop.

you gots to drop 'em in the correct order

i can't tell from your column names what the FKs are

instead of DESCRIBE, please do a SHOW CREATE TABLE for each table