PHILADELPHIA (WPVI) --Whenever there's an attack like the one in Brussels, it always raises fears of whether or not it could happen here at home.
Action News spoke with US Counter Terrorism expert Ed Turzanski about what most people here in Philadelphia have on their minds: Could an attack like the one in Brussels happen here in the United States?
These recent bombings, he says, could be evidence that ISIS is more powerful and potentially more dangerous than previously thought.
Turzanski explains, "ISIS right now is much more capable and lethal than any terror organization that preceded it, because its reach is extraordinary."
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Turznaski says both Belgium and the U.S. should be on guard, preparing for more attacks as ISIS radicals and sympathizers expand their efforts.
"There is nothing that happens in Europe, relative to ISIS and terror activity, that isn't going to come here in one form of another," he said.
Four days after the mastermind of the Paris attacks was arrested, the bombings in Brussels are believed to be revenge. Turzanski says the open targets and timing are no surprise.
He says, "They were pretty certain there would be a retaliatory strike or else there were already plans underway for an attack. It would be much more difficult to do here. I don't want to say it would be impossible."
And Turzanski warns there is a possible hotbed of jihadist activity right in our nation's heartland, which he believes is a breeding ground for terrorists.
Turzanski says, "ISIS has an international brand name and they have had tremendous success in getting people to be a part of their movement."
And refugees and immigrants, he says, are being actively recruited. Our government, he says, needs to be vigilant in fighting the influx of radicals inside our borders.
"Over time, if this activity isn't fought in a very clear way, chances are you are going to have more of it," he said.
And even with more advanced anti-terrorism efforts in the U.S., Turznaski says it would be nearly impossible to secure all soft targets, like airports, bus stations and train stations. He says based the vast nature of those public areas and the sheer inconvenience would be crippling.