Muslim leaders in the UK have warned against laws that automatically brand British fighters in Syria as terrorists.
It comes as Home Secretary Theresa May launches a campaign today to discourage young men from going to fight in Syria and Iraq. A short film will focus on the distress it can cause their families.
But some in the Muslim community have told Sky News the Government's legal stance on fighting abroad could "increase the risk" to the UK.
Abdullah al Andalusi, a senior researcher at the Muslim Debate Initiative, said: "It's hypocritical of the UK Government to expect Muslims not to go, if they feel they want to fight in a just war.
"Bertrand Russell, George Orwell - they went to the Spanish civil war, people were going to fight Gaddafi in Libya and that was all fine.
"So I worry that the British Government should dictate to us what is fine and what is not fine about where to go, when the situations could be arguably very similar in all those places."
He added: "Obviously there are some terrorist groups in Syria and Iraq but if we start punishing everybody it only adds a grievance which actually increases the risk (to the UK).
In the late 1930s, British nationals fought against a fascist rebellion in Spain - and under today's laws they would probably be classed as terrorists.
The 2006 Terrorism Act stipulates that weapons training and fighting in rebel groups against the foreign state can be treated as if acts of terror in the UK. The Government is seeking to strengthen this law with its Serious Crime Bill.
Some British fighters in Syria have argued they are only acting where the West failed to act following President Bashar al Assad's alleged use of chemical weapons on his own people.
Security Minister James Brokenshire told Sky News: "I understand that people want to assist but the point is that by doing so they may put their own lives at risk because of the situation on the ground, and put themselves at risk of exploitation by extremist and terrorist groups such as the Al Nusra Front and ISIS.
"We know that there are those who have been involved in terrorism in Syria and that's why we've seen prosecutions and why we must remain vigilant, because of the potential threat posed by those individuals who have been exposed and therefore what they may do on their return to the UK."
However, Maulana Shahid Raza, trustee of the British Muslim Council, told Sky News: "Everybody should not be branded a terrorist unless it is proven. So my request to the politicians is we need their support and we need their help in order to resolve this crisis among a section of our young people."
Maulana Mohammed Madni, chairman of the Mosques and Imams National Advisory Board, said: "Just going there, they are endangering their lives but they are not necessarily terrorists."
With so many groups in Syria fighting each other, the Government warns that Brits who think they may be joining a battle against the Assad regime are being sucked into a quite different ideological battle controlled by terrorist groups.
The Muslim community is also united in warning people not to go.