The images out of Nice are horrifying, and for most, the implications are just as hard to digest.
Terror experts say the latest attacks signal a troubling trend.
Former FBI agent Stuart Kaplan says it's obvious - the game is changing.
"At one point we were more concerned about tracking groups or organizations," Kaplan says. "And now we have individuals who are sympathizing with this propaganda through ISIS."
Kaplan says the nature of these attacks has also changed.
Soft targets with less police presence are now the venue of choice - like malls, movie theaters and nightclubs.
The weapons used - not bombs - but guns and vehicles.
"We're dealing with individuals that are not necessarily going about and utilizing sophisticated means," he says.
Kaplan points out that now we know these attacks can happen anywhere.
As a result, he says local law enforcement needs to be prepared - and that may require some level of militarization.
"Unfortunately, we're going to have to embrace that police officers are going to have to have tactical gear on, have the necessary weapons."
Kaplan says even with everything going on Americans shouldn't live in fear - but instead be vigilant - especially out in public.
"Think about your exit strategy, or if God forbid something was to happen, what would be the first thing I would do?"
Kaplan also stresses that law enforcement should have more freedom to monitor social media - so they can keep up with online chatter before attacks happen.