Below is the list of tables from the database along with their columns and datatype. Need to generate an accurate SQL query for the question.
Only use the columns present in the respective table. Only use the columns which are required to generate the SQL query. Only use table joins if required and not otherwise.

### Tables ###
TABLE: CREATE TABLE table_18424435_4 (us_air_date VARCHAR, canadian_viewers__million_ VARCHAR)

### Question ###
What was the air date in the U.S. for the episode that had 1.452 million Canadian viewers?

### Accurate SQL ###

SELECT us_air_date FROM table_18424435_4 WHERE canadian_viewers__million_ = "1.452"