Time Cwabs!

I seem to have gotten hold of a time machine, and have been using it to try to make a better future (future being the past more closely aligned to the present) for my friends. Anyone have a mission for me? So far I've tried to stop the Iraq war, and warned folks that the police might be coming for them by mistake, and to use nails instead of blowtorches when installing shingles, among other things.

The burdens of fictional time travel.

Playing with the time machine was cute for a while,
but then I wanted to go back and tell someone
to get to the hospital immediately,
and not wait for the doctor's appointment the next day.

And,

naturally,

I couldn't.