No. There was no war in Australia while Edmund Barton held office.
Edmund Barton was the Prime Minister at the time of World War because in the year of federation Edmund Barton was elected first Prime Minister of Australia and that was the time of WW.
No.
Any country with an army or militia will send there troops into a conflict or war.
The president could send troops overseas without a congressional declaration of war.
Reconstruction
Into Spain and Portugal in the Peninsular War.
1. amount of troops 2. Only Congress can declare war, the president can send a limited amount of troops to fight (conflict)
Great Britain did not send troops to Vietnam during the war.
The purpose of the UN troops was to try to end the Lebanese Civil War.
Brazil did send a division in World War II. It was equipped by the US and served in Italy.
The president could send troops overseas without a congressional declaration of war.