Dubbed the "tartan terrorist," Adam Busby has used different methods, but his aim has long been the same -- to send a message to British leaders that his native Scotland deserves independence.
Why, then, did the Dublin resident, who was indicted this week by a federal grand jury for emailing a series of 40 false bomb threats last spring, target the University of Pittsburgh?
Officials here won't discuss a motive, and it's unclear whether Mr. Busby, a 64-year-old who has multiple sclerosis and uses a wheelchair, will face trial in the United States.
U.S. Attorney David J. Hickton refused to say Friday whether his office has begun extradition proceedings against Mr. Busby or even whether it plans to do so.
There are a number of reasons extradition from Ireland might not be sought, not the least of which is the apparent difficulty in being successful there.
The Irish Times reported in March that a judge denied a U.S. extradition request on the grounds that crimes committed in Ireland but affecting other countries should be prosecuted in Ireland.
The ruling, denying the extradition of Sean Garland, an Irish man charged in a conspiracy to forge U.S. dollars, will likely make extradition difficult in cybercrimes such as the emailed bomb threats affecting Pitt.
The newspaper reported that an unidentified extradition law expert said the effect of the "Garland ruling" was that extradition no longer can be based on a whole slew of crimes that are also criminal offenses under Irish law.
"Julian Assange could not be extradited to the U.S. from Ireland," the paper quoted the expert as saying, referring to the controversial founder of WikiLeaks.
Adding more complications is the fact that the United States is not the only country interested in extraditing Mr. Busby to face hoax charges. So is his native Scotland.
According to a July Daily Mirror article, Mr. Busby made calls and sent text messages in late 2009 to media and social support groups in Scotland threatening to contaminate drinking water supplies in England and to send packages containing dangerous substances to then-Prime Minister Gordon Brown.
A spokeswoman for Scotland's Crown Office said in an email that Mr. Busby, who was detained in Dublin last month on a European arrest warrant, is the subject of extradition proceedings, but she would not comment further.
His legal problems in Scotland will likely factor into a decision here whether to seek extradition, said Jules Lobel, a law professor at the University of Pittsburgh.
"If they thought the most likely place he would be extradited and tried would be Scotland and they're reasonably confident in their legal system, the likelihood would be they wouldn't extradite him," he said.
In addition to that, Mr. Busby's age and health would be issues arguing against extradition, said Wes Oliver, a Duquesne University law professor.
On the other hand, Mr. Oliver said, an argument to seek extradition might be to send a message about such crimes.
For now, Mr. Busby is being held at Wheatfield Prison, a medium-security facility for adult males, as he awaits a hearing on the European arrest warrant, according to a statement emailed Friday from the Irish Prison Service's press office.
The prison is in Dublin, across the Irish Sea from Scotland, where Mr. Busby took an early interest in fringe movements for Scottish independence and eventually formed the Scottish National Liberation Army, a separatist movement.
Mr. Busby was born into a middle-class family in the Scottish county of Dunbartonshire, according a study of the SNLA written by David Leslie, a freelance journalist and true-crime author who worked for News of the World for more than 40 years.
Mr. Busby and the SNLA committed "low-level violence" against English people in Scotland in the 1970s and early 1980s, according to a 2002 BBC News report. The violence reached its apex with letter-bombs sent to English officials, including then-Prime Minister Margaret Thatcher in 1983. The same year as the letter-writing campaign, Mr. Busby fled to Dublin, the BBC News article said.
Since then, Mr. Busby has directed numerous hoax threats at a wide range of targets and has been in and out of Irish prisons on the charges.
According to a July article in the Daily Record, Mr. Busby contacted Scottish media groups in 2010 to make threats about contaminating drinking water supplies in English towns.
Most recently, Mr. Busby was sentenced in 2010 for sending hoax bomb threat emails to Heathrow airport, according to The Irish Times article. Investigators showed that he sent the emails from computers in a public library in Dublin.
Mr. Busby served 18 months of his 2-year sentence and was released from a Dublin prison in January, according to an emailed statement from the Irish Prison Service.
He was remanded to prison in July for the European arrest warrant issued by Scotland and is awaiting an Oct. 2 hearing before the High Court in Dublin, according to Ireland's Courts Service media office.
Mr. Busby is being represented by the Dublin law firm of Michael J. Staines & Co. Other than to confirm their representation of Mr. Busby, the firm declined any further comment Friday.
The conclusion to the bomb threat mystery -- with a suspect indicted here but imprisoned across the Atlantic Ocean -- may have raised more questions than it answered.
In a strange way, however, it is "a perfect cap" to the spring saga, said Ben Livingston, a rising Pitt senior who described the weeks of false bomb threats, and the idea that a university could be so disrupted by them, as baffling.
"It almost seemed like there couldn't be a logical conclusion to it. It had to be far-fetched."