-- Create tmp
$ aws s3 sync s3://bucket1 s3://tmp --source-region us-west-1 --region us-west-2
$ aws s3 rb s3://bucket1 --force
-- Recreate bucket1 in us-west-2, but you might have to wait due to caching
$ aws s3 sync s3://tmp s3://bucket1 --source-region us-west-2 --region us-west-2