Yeah, yeah, I heard this same thing 30 years from now.
Issac Asimov wrote a good short story about exactly why you would NOT want to invent a time machine, or, as in his story a "Time Viewer". When does the past start? A century ago? A decade ago? Last week? Yesterday? One microsecond ago is a good start. If you could build a machine that just "views" time in the past, you'd have the perfect spying machine...................