How to add column from old_table to new_table?

Hi,

I have an old_table with two columns: "id" and "old_attribute". I have
new table with the columns "id" and "new_attribute". 

old_table and new_table contain exactly the same id's. Now I want to
copy all the old_attribute from old_table to the corresponding
new_attribute in the new_table

Is that possible in a SQL script (pgadmin or psql console?) and if so,
what is the syntax in this example? 

I have tried something as:

insert into new_table(new_attribute) 
value( select old_attribute from old_table, new_table where old_table.id
= new_table_id)
where new_table.id = old_table.id

TIA

-- 
Groeten,

Joost Kraaijeveld
Askesis B.V.
Molukkenstraat 14
6524NB Nijmegen
tel: 024-3888063 / 06-51855277
fax: 024-3608416
e-mail: J.Kraaijeveld@Askesis.nl
web: www.askesis.nl