Modern acts of terrorism were less frequent but were becoming far more violent, a visiting American academic said.
Dr Walter Enders from the University of Alabama is working at QUT for the next month as an adjunct professor in the School of Economics and Finance and is considered a leading terrorism expert after studying the field for almost 15 years.
Dr Enders has direct access to a database called ITERATE that details every publicly available transnational terrorist act in the world since 1968.
"Although you wouldn't know it if you followed the media, the number of terrorist events has actually come down fairly dramatically," Dr Enders said.
"However, the proportion of events that have deaths or casualties associated with them has gone up markedly. The typical terrorist incident is now way more deadly than it used to be.
"Going back over the years if a bomb went off outside some American Express office in Paris it would make the newspapers but these days I don't think that it would receive any publicity.
"In order to get their message out, terrorists have had to continually escalate the levels of violence."
He said the nature of terrorism had changed and moved towards more of a religious basis.
"Terrorists used to want to change the state of the economic system, they were concerned about needs of poor and the world's needy. They had a message and they wanted to convert people to a Marxist-based philosophy," Dr Enders said.
"These people today don't want to convert anyone so they don't mind being brutal and they are not particularly afraid of getting hurt or getting killed."
He said based on the data collected since 1968, "it's possible" that Australia could be a terrorist target after joining the United States in the war against Iraq.
"If I were to project the patterns of the past, countries that have cooperated with the United States have seen the same types of retaliation that the United States has seen."