If you *dont* use casacde, what would you expect the child tables to then point to ?

You must either use 'cascade' or explcitly drop the foreign key constraints. 'disable' is not sufficient, eg

SQL> create table t1 ( x int primary key ) ;

Table created.

SQL> insert into t1 values (1);

1 row created.

SQL> create table t2 ( y int, constraint fk foreign key ( y ) references t1(x));

Table created.

SQL>
SQL> drop table t1;
drop table t1
           *
ERROR at line 1:
ORA-02449: unique/primary keys in table referenced by foreign keys


SQL> alter table t2 disable constraint fk;

Table altered.

SQL> drop table t1;
drop table t1
           *
ERROR at line 1:
ORA-02449: unique/primary keys in table referenced by foreign keys