I've had issues getting steadily worse all day across domain since ~9 am est or so. I just received this from Google as part of an auto reply to support ticket.
"Thanks for your patience.
Please read below for updates on the status of your issue:
Updates since last message:
This issue has been partially resolved for some users. We expect it to be fully resolved within the next hour. The issue caused severe delays sending emails, especially emails with large attachments. It also caused delays in loading Drive files with large images.
The delays were caused because of a problem with an undersea cable. All parties involved are actively working to:
1) Redirect traffic and add additional capacity to resolve the immediate issue.
2) Fix the problem with the faulty undersea cable.
"
Wild guess: google routes non-latency-critical US traffic like SMTP outside the US so the NSA's beam splitters can more easily claim intercepted domestic data as "international".
"Thanks for your patience.
Please read below for updates on the status of your issue:
Updates since last message:
This issue has been partially resolved for some users. We expect it to be fully resolved within the next hour. The issue caused severe delays sending emails, especially emails with large attachments. It also caused delays in loading Drive files with large images.
The delays were caused because of a problem with an undersea cable. All parties involved are actively working to: 1) Redirect traffic and add additional capacity to resolve the immediate issue. 2) Fix the problem with the faulty undersea cable. "