Were the relevant Laws and Regulations different, in the time-frame that the Bush emails were supposedly lost or destroyed, versus the era when the Clinton emails were supposedly created and transmitted and archived and vetted?
If "yes", and relevant Laws and Regulations allowed for a more lenient treatment or sanction at the time of the Bush email 'scandal', then, we're done here.
If "no", did George W. Bush personally and publicly declare uncategorically that no covered emails existed or were transmitted through such systems?
Finally...
What does this have to do with whether or not Hillary Clinton broke the law, in (1) using her personal email server(s) for State Department business, (2) processing Top Secret communiques through personally-controlled server(s), (3) making false public declarations about those Top Secret communiques, (4) deleting Top Secret emails on personal server(s), and (5) lying to Congress about it.
Just because the Bush Administration may (or may not) have done something similar, in an earlier time, most likely covered by earlier and more lenient Laws and Regulations, has absolutely NOTHING to do with whether or not Hillary Clinton is guilty of (1) thru (5) above.
"
The other guy did it earlier, so I get to do it, too." - that 5th-grade recess-yard shit isn't gonna cut it in our present-day charged political climate.
Try another Deflection Tactic to try to protect one of your own, 'cause
this dog won't hunt.