There is a lot of garbage posted here. If the australian victims were or are muslim nothing would have changed there still would have been a minutes silence. Australia have always mourned their citizens killed in unusual circumstances with a minutes silence, if other countries don't do the same then that is not a reason for Australia to stop. There is nothing political about it at all, it is a way to pay respect for the fallen and to let their family know that the nation grieves with them.
No one has to be a part of the minutes silence, its up to the individual to decide if they want to pray, just observe the minutes silence or ignore it all together.
We as a nation join together to pay our respects to a fellow citizen/s that has fallen, it is one of us that has fallen and we rally not for politics, religion or wealth but for the mother, father, sister, brother, workmate, community member. No we don't do it when its a American, Indian, Pakistani or any other country but we will at all times join them if they pay their respects to their fallen.
You are indeed a very desperate person to bring politics or religion into it.