The federal charges filed this week against a Harford County man accused of pledging allegiance to the self-declared Islamic State come as rising fears of terrorism — and growing anti-Muslim rhetoric — have returned to dominate public discussion.
Since the shootings that left 14 dead in San Bernardino, Calif., polls show that fears of future attacks have risen to levels not seen since the weeks after Sept. 11, 2001.
President Barack Obama has given a series of addresses to detail his strategy for fighting the Islamic State. Donald Trump's proposal to bar Muslims from entering the United States has drawn wide condemnation — while his poll numbers among likely Republican primary voters climb.
The suspects accused of plotting or carrying out attacks on U.S. soil since Sept. 11 represent a minuscule fraction of the nation's several million or so Muslims.
Muslim leaders in the United States routinely condemn attacks, and work with authorities to identify individuals at risk of becoming radicalized.
The challenge, analysts say, is that authorities are looking for needles in a haystack.
"There are no mosques that I know of where there have been a huge number of youth or adults who have been radicalized," said Robert L. McKenzie, a former State Department official. "Part of the problem, as we saw with the San Bernardino attacks, is we have isolated incidents."
Investigators say the couple who carried out the attacks in San Bernardino were radicalized years before the shooting.
In Maryland, prosecutors say Mohamed Elshinawy, 30, of Edgewood, had extensive online communication with contacts abroad and received almost $9,000 to carry out attacks in the United States.
The Edgewood man said in online conversations that he had many targets and discussed building an explosive device, the FBI says in court papers.
The FBI said agents watched as Elshinawy deposited some of that money, which was wired to a convenience store near his home, and brought him in for an interview.
His case ultimately played out like so many others, with authorities intervening long before any attack could be carried out.
Elshinawy has agreed to be held in custody, according to court records.
His attorney, deputy federal public defender Joseph Balter, said the case is still at an early stage. "We hope the public will withhold judgment and let the legal process take its course," he said.
Elshinawy once worked for a Baltimore Sun contractor as a paper delivery worker, a spokeswoman for the Baltimore Sun Media Group said.
Polls published by The New York Times, NBC and the Wall Street Journal in the last week show that terrorism is now the leading concern among Americans.
Zainab Chaudry, Maryland outreach manager for the Council on American-Islamic Relations, said her organization urges Muslims to speak up if they are concerned that someone they know is interested in extremist ideologies.
She also urges authorities not to treat all Muslims with suspicion. "Any solution to countering violent extremism must have the Muslim community at the table," she said.
McKenzie, now a researcher at the Brookings Institution, said the government should look more closely at people who have shown interest in ISIS or other extremist groups online, and try to step in before they commit a crime.
"We can easily find them," he said. "The question is why aren't we thinking about policies to try and intervene with these individuals?"
Chaudry said American Muslims have faced an "unprecedented backlash" in recent weeks, including vandalism to mosques, death threats and physical attacks. "It's been an absolute nightmare," she said.
Elshinawy is the latest in a series of Maryland men accused in terrorism cases.
Malik John surrendered to authorities in Somalia after traveling to fight with the militant group Al-Shabab, Reuters reported last week.
Former soldier Craig Baxam of Laurel was sentenced last year to seven years in prison after making a similar trip.
Antonio Martinez, who lived in Baltimore and Baltimore County, was sentenced to 25 years in 2012 after he attempted to set off what he believed was an explosive outside a military recruiting center in Catonsville. The dummy bomb had been provided by an undercover FBI agent.
Mohammad Hassan Khalid, a teenager from Ellicott City, was sentenced last year to five years in prison for his involvement in a plot with Colleen LaRose, known as "Jihad Jane," to kill a Swedish cartoonist who had drawn the head of the prophet Muhammad on the body of a dog.
Majid Khan, a graduate of Owings Mills High School, was arrested in Pakistan and detained at Guantanamo Bay. He pleaded guilty in 2012 to murder, espionage and conspiracy for his role in the deadly 2003 bombing of a hotel in Indonesia and plots to assassinate Pakistani President Pervez Musharraf and blow up gas stations in the United States. He awaits sentencing.