There have been conflicting reports over the past week about the likelihood of an attack by ISIS within the United States. Even high-ranking officials within the Department of Defense have raised a level of concern not heard for some time now.

A few days ago, Secretary of Defense Chuck Hagel and Gen. Martin E. Dempsey, chairman of the Joint Chiefs of Staff, stated in a press conference that ISIS was a group that was "apocalyptic ... beyond anything we have seen."

This is true.

ISIS, or ISIL, or the Islamic State (however you want to refer to them) is a group of dedicated, almost maniacal, jihadists focused on disrupting the power structure in the Middle East region at a minimum, and establishing a caliphate that - stated in their self-proclaimed five-year plan - will reach to Spain and include eastern portions of Europe up to Austria.

Chilling? Indeed. They are more organized, better funded and resourced than al-Qaida ever was or has been, and are more ambitious than al-Qaida in the Arabian Peninsula.

A report from the Department of Homeland Security and the FBI warns the potential for retaliation within the United States by ISIS sympathizers has led to heightened concern. Presumably, such attacks would be in response to the air attacks the United States has unleashed upon the group within Iraq as well as the imminent attacks in Syria.

The security warning notes, "It is difficult to predict triggers that will contribute to (homegrown violent extremists) attempting acts of violence … (Lone wolf terrorists) present law enforcement with limited opportunities to detect and disrupt plots, which frequently involve simple plotting against targets of opportunity."

It is prudent that we remain alert and vigilant, but also just as important to not overemphasize the threat or engage in exaggeration and hyperbole. These warnings, however, do not mean any attack is imminent. Simply, they raise concerns that the nation must be on a heightened alert for such possibilities.

As White House Press Secretary Josh Earnest noted yesterday, "We are concerned about the threat that is posed by ISIL, but it is the assessment, as stated by the chairman of the Joint Chiefs of Staff, by the intelligence community, that there currently is not an active plot underway to attack the U.S. homeland by ISIL."

Carefully walking the line between vigilance and overreaction is a difficult effort. It remains to be seen how far ISIS will move toward engaging the West. It is crucial to note the FBI bulletin does not say ISIS is developing a plan to attack the United States, but rather the immediate threat is one of a lone wolf, or sympathizer, within the country acting on his own.

Protecting the citizens must be the top priority of government and policy makers. ISIS is a threat, and one we should be prepared to prevent from gaining any further momentum. We must be on guard to prevent any lone wolfs from attacking the homeland. But, as law enforcement and homeland security teams prepare for any potential attack, we must be careful to not overreact to such warnings and overstate the immediate threat from the overseas organization.

Glenn Sulmasy is a Homeland and National Security Law Fellow at the Center for National Policy in Washington D.C. and a professor of law at the U. S. Coast Guard Academy. He is the author of "The National Security Court System - A Natural Evolution of Justice in an Age of Terror." The views expressed are his own.