Sen. Dianne Feinstein (D-Calif.) and Sen. Charles Schumer (D-N.Y.) at the Senate Judiciary Committee markup of the "Assault Weapons Ban of 2013", on March 7, 2013. (AP File Photo)

(CNSNews.com) - Gun control advocates said on Monday they're going to push "to finally close the terror gap once and for all" by barring gun sales based on the FBI's suspicions about how a gun will be used.

"If the FBI believes there's a reasonable chance someone is going to use a gun in a terrorist attack, it should be able to make that determination and block the sale," Sen. Chuck Schumer (D-N.Y.) told a conference call on Monday.

"And now that we have lone wolves inspired by ISIL, even more the reason to do this than ever, ever before. It made sense 10 years ago. It makes even more sense today."

Schumer and the Democrats joining him on Monday's conference call want to bar gun sales to people on the government's secret terror watch lists.

They criticized congressional Republicans who voted to block such a bill following last year's terror attack in San Bernardino.

"The bottom line is these attacks are preventable," Schumer said. "Mass shootings are the status quo. And one of the main reasons is that Congress has voted against sensible gun safety measures. It's that simple."

Schumer said Democrats will make a "renewed effort to close the terror gap." Yet in the same conference call, Schumer admitted, "You can get a semi-automatic weapon with a whole lot of clips, OK, even if we banned assault weapons, which I'm all for."

Sen. Dianne Feinstein (D-Calif.) said the bill she sponsored in 2015, and is proposing again, "would close a loophole."

"There are currently nine categories of people who are prohibited from buying guns," she said. "And those categories include felons, fugitives, domestic abusers, among some others. But they do not include known or suspected terrorists. And the bill we're talking about today simply would close that loophole.

Feinstein read the specific language from line 14 on page 2 of the bill: "And it says,'The Attorney General may deny the transfer of a firearm ...if the Attorney General, one, determines that the transferee is a known or appropriately suspected to be or have been engaged in conduct constituting in...preparation for, in aid of, or related to terrorism, or providing material support or resources for terrorism. And, two, has a reasonable belief that the prospective transferee may use a firearm in connection with terrorism.'

Feinstein said the current system of background checks "really isn't enough," because it doesn't bar "known or suspected terrorists" from buying a gun.

A few Republicans also supported Feinstein's bill. Rep. Peter King, a New York Republican, sponsored a companion bill in the House last year. And of the 32 senators who originally cosponsored Feinstein's bill in 2015, one was a Republican (Mark Kirk of Illinois). Two were Independents (Angus King of Maine and Bernie Sanders of Vermont).

In response to a reporter's question, Sen. Schumer said Feinstein's bill "is carefully crafted" to bar gun sales to people, "even if someone is not presently on a watch list." If the FBI determines that the two criteria [mentioned above] are met, "they can prevent that person from buying," Schumer said.

"There is also, I might add, for those concerned with the rights of people -- and we all are -- a very quick and speedy appeals process."

Feinstein's bill would allow a person who believes he has been mistakenly prevented from buying a firearm to learn of the reason for the denial, and then to challenge the denial, first administratively with the Department of Justice, and then through a lawsuit against the Justice Department.

Of course, that would take time and money on the part of wrongly denied Americans.

Schumer said he believes Republicans, in this "difficult political season," "are going to find it very, very difficult" to vote against Feinstein's bill. "We've had two incidents, San Bernardino, and now Orlando, where this type of legislation would be relevant, making sure that terrorists don't get guns."

Schumer did not rule out another attempt to ban what he calls "assault weaons," but he said in the current environment, Feinstein's bill is "the most effective piece of legislation we can pass."

"You can get a semi-automatic weapon with a whole lot of clips, OK, even if we banned assault weapons, which I'm all for. So I don't agree with you the assault weapons ban is the most effective way to deal with terrorism," Schumer told a reporter.



"I'm certainly for it. I think we should do it, and it's something we will seriously explore. But this legislation, as I mentioned…"has the greatest chance of passing. We want to get something done."

Schumer said Feinstein's bill could be attached to the Commerce, Justice, and Science appropriations bill, which is now on the floor. "That's one possible place to add this bill. But one way or another, we're going to push to get the terror-gap bill passed."