"The powers not delegated to the United States by the Constitution, nor prohibited by it to the States, are reserved to the States respectively, or to the people."
dry run for a bigger attack
The 9/11 conspirators didn't bother with any dry runs and succeeded beyond their wildest dreams.
Terrorists aren't a cautious or methodical bunch; they're audacious. Dry runs are not only for wimps but they also alert your adversary to your intentions.
There's no tax dodger like an Italian tax dodger.
A person with one watch knows what time it is; a person with two watches is never sure. Proverb