Err on the side of caution?
Why can’t the CDC and the government do just that?
Under what study would scientists have concluded that anthrax spores would remain neatly confined inside envelopes?
What envelope have you ever known that sealed perfectly?
Were I a relative of one of the two postal workers in Washington who probably dies from anthrax, I’d be asking why the hell they didn’t quarantine and test post offices that might have routed the Daschle mail before allowing people to work.
It seems to me that when you’re dealing with something you’ve never seen before, you need to act with caution rather than confidence.