A scam email was sent directly from a gmail account (Google's IP in the message header below my ISPs).

The title of the scam:
***You Have won EUR820,000.00***

Part of the body (minus contact info):
Hello !

You have been chosen to collect EUR820,000.00 in our Promotional Draw.

Please read attached message for details.

Congrats!

The email came into my Earthlink account where it was promptly put it into the known spam folder.

So Earthlink and other ISPs easily detect this as a scam (spam) but Google can't detect it before sending it out.

Why is that?

The obvious subject "You Have won" and words like lottery, lotto, Congrats, etc should be easy to detect if you scan outgoing emails before they are sent.

Obviously spammers want to get lots of emails out so I'm sure it's not the first or only email sent from this gmail account.

On top of that, this account is probably not that old. So all of a sudden a new account starts sending out "you won" messages and Google is not smart enough to detect that?

It should be trivial for Google to be able to detect such accounts and terminate them automatically because the messages are being sent from their servers.