Dr. Sebastian Gorka, Maj. Gen. Matthew C. Horner Distinguished Chair of Military History at the US Marine Corps University and Katharine C. Gorka, president of Threat Knowledge Group, have both agreed that the ISIS threat to bomb targets in the U.S. is real and warned the government to be prepared.

In an article written for the New York Post, said that the latest trends in law enforcement and intelligence indicate that America is not safe from terrorist attacks, instead the probability of a Paris-style ISIS attack last Friday that killed more than 120 people and injured hundreds more, "has dramatically increased."

"As part of its support to law enforcement, the Threat Knowledge Group has been collecting and analyzing the open-source information on ISIS arrests in the United States," Sebastian and Katharine write. "Since ISIS, the organization that used to be al Qaeda in Iraq, captured the city of Mosul last year and declared the creation of the new caliphate, scores of people have been arrested in America in plots connected to the new 'Islamic State,' and FBI Director James Comey has already testified that there are ongoing ISIS investigations in all 50 states."

According to the two, U.S. law enforcement agencies have arrested 74 adults and eight minors and killed four on U.S. soil over the past 20 months suspected of connections to ISIS. The figures translate to a 300 percent rise in terrorist arrest in the U.S. since the September 11, 2001 attacks.

But while a majority 48 percent of those intercepted suspected terrorists have signified their intentions to leave the country and join Abu Bakr al-Baghdadi and ISIS in the Middle East, an alarming 28 percent, of one-third of all those arrested in the U.S. do not want to leave the country but rather want to stay to kill Americans on U.S. soil to better serve Allah and ISIS leader Abu Bakr.

The writers said, "They would better serve the new theocratic empire of Islam and strike terror into the heartland of the enemy. To this, we must add the unclassified estimates that put the number of foreign fighters globally recruited by ISIS at more than 22,000. Of those, 4,000 are estimated to be Westerners - including Americans - on Western passports that allow them full freedom of movement. As a result, the threat to America is clear.

Immediately after the Paris attack ISIS has released video threatening to attack the U.S. capital and other states and warned that the attacks in Paris are "just the beginning," ABC reported.

"It's not just Europe. I think we here in the United States need to be obviously quite vigilant. Their agenda is to kill. Pure and simple," said CIA Director John Brennan told ABC. The country is currently operating under a heightened security level but maintains that there hasn't been a "specific, credible threat made to the homeland," despite ISIS' recent message about Washington, D.C.