Yet again we have seen the bombing of innocent people by Islamic State. And yes, it could happen here. The common factors in every country that has suffered terrorist attacks from within are high youth unemployment and the rise of right-wing political ideologies.
These two factors more than any other align with the radicalisation of young people and the conversion to radical Islam. How long will it take for our leaders to realise that giving constructive opportunities to our young people and silencing those who would demonise minorities is the only way out of this mess. 
Stephen Broderick Avalon
Charlie Hebdo and the   November 2015 massacre in Paris. New Year's Eve 2015 in Cologne. Where next? Australia, perhaps? Pandering and mollycoddling Islamists does not work. They are out to dominate the Western world. This is not a fanciful idea: it is reality.
Our government and its advisers can't grasp that concept. They are too engrossed in being politically correct. It is time for our leaders to get real. It is not a perfect world.
Graeme Brewer
Biggera Waters (Qld)
The authorities in Belgium or anywhere else will need a political solution to the bombings. For every extremist apprehended there'll be 10 more lining up to take their place.
Lars Newman Fairlight
All across the social media landscape today, small-minded xenophobes will be exploiting the horror in Belgium to argue against asylum seekers. "We don't need 'those kind of people' coming here," they will say.
Even my cat can see that refugees and asylum seekers are the ones running away from "those kind of people".
It will take a political leader of strength and depth to seize the narrative and redefine refugees for what they are, ordinary people with real lives whose world was turned upside down. I'm not betting on Malcolm Turnbull or Bill Shorten showing either of those qualities.
Shayne Chester Potts Point
Has anyone noticed the different reaction from Western nations regarding the Belgian bombings compared with when multiple bombs were detonated in Turkey? There was barely a comment from politicians and minimal media coverage. I fail to understand the difference.
Stephen Rayner Westleig
After   September 11, "we" declared a "war on terror". Since then, the frequency of terrorist attacks has increased. After 15 years, it is clear that war, bombings, and invasions have been counterproductive. Reminds me of the "war on drugs". Is it not time to try something else, such as considering what's generating the desire to commit these atrocities?
Peter Lees McMahons Point
"Je suis Belge" is probably the harshest response we can expect from Europe to the outrage in Brussels.
George Fishman Vaucluse
The only good thing about suicide bombers is that they cannot do it a second time. Sadly, they do inspire others to do that for them.
Donal O'Sullivan New Farm (Qld)
One thing that could be done to improve airport security is not allow anyone entry to a terminal building without a valid ticket or a security pass, as is the case in some parts of Asia.
Patrick St George Goulburn
People constantly refer to terrorist attacks as "cowardly". How do they define "drone" attacks ?
Gary Frances Bexley
Following the attacks at Brussels airport it was reported "the CCTV images were unclear".
Every time CCTV images are shown of alleged perpetrators of serious crime, the images are always unclear. It is difficult to positively identify the subject of the image.
Can someone please advise me why this is so, especially when there is technology in place that can read a motor vehicle number plate from outer space? Surely in this modern age, this technology cannot be prohibitively expensive, especially where there is potential for massive loss of life?
Michael Slocum Ascot Vale
Immediately after what we now call World War I, the Manchester Guardian used the term World War II in reference to a hypothetical future war. It wasn't till about 1942 that the term was used for the 1939-45 war, or that the First World War got that name. I wonder when the current "war on terror" will be seen as World War III.
Ed Matzenik Maitland