From CNN: ISIS-Related arrests in the U.S.

60 arrests in 2015
15 arrests in 2014
26: average age of suspects
40% religious converts
27% planned attacks in U.S.

But then if you compare it to all gun related deaths in the U.S. NOT FROM TERRORISM

it is a different story: quote from:
United States under the Sub heading Crime from Wikipedia:
In 2012 there were 4.7 murders per 100,000 persons in the United States, a 54% decline from the modern peak of 10.2 in 1980.^[358] In 2001–2, the United States had above-average levels of violent crime and particularly high levels of gun violence compared to other developed nations.^[359] A cross-sectional analysis of the World Health Organization Mortality Database from 2003 showed that United States "homicide rates were 6.9 times higher than rates in the other high-income countries, driven by firearm homicide rates that were 19.5 times higher."^{[360][dated info]} Gun ownership rights continue to be the subject of contentious political debate.
end quote from:
wikipedia subheading United States subheading law enforcement and crime:

So, there are very very few terrorist attacks or attempts of attacks. However, compared to other high income countries there are firearm homicide rates at 19.5 times higher than the average for high income countries here in the U.S.

However, the other way to look at this is education has markedly reduced the percentage of people being killed from violence of all kinds since 1980 when there was a peak of 10.2 murders per 100,000 people whereas in 2012 this had reduced by more than 1/2 to 4.7 murders per 100,000 people.

So, I would say education and sophistication were the main factors in reducing violence of all kinds and deaths from 10.2 per 100,000 in 1980 to 4.7 per 100,000 people in 2012.

However, then one has to assimilate the fact that the U.S. has 19.5 times higher firearm homicide rates than the average for all high income countries on earth. But, generally speaking these deaths are located in barrios and other lower income areas of the U.S. for the most part except for mass shootings in Schools and Universities.

However, for me, it mostly shows the average person and alcohol and drugs is a bad combination when combined with domestic violence.

So, if people were more disciplined about firearms they might be able to have them and not use them so much on each other in a fit of anger or by accident.

So, are people generally safer with firearms in the country?

Looking at these statistics I would have to say the answer is actually "No".

However, do people "Feel" safer with firearms? Most people who know how to use them might say, "Yes".

So, your safety regarding firearms might depend upon your domestic situation and how you are dealing with each other in your family. How mentally ill or incompetent are some members of your family. Do they have access to guns?

These are all very important questions if you want to stay alive.

Another question is: "Do alcoholics or drug abusers live in your home and have access to guns?"
Do alcoholics or drug abusers live in neighboring houses to yourself and have access to guns?

It likely doesn't matter whether these people are police officers or security officers or soldiers who have access to guns if they are alcoholic or drug abusers or are having PTSD. All of these people if in mental or emotional distress could be a threat to the community while drinking or on drugs or during a severe domestic dispute.