Interesting propaganda or not: it was certainly psychology to "find a common enemy" to get squabbling factions of society to unite. I remember my parents talking about the allies having taught Japan how to make good steel for weapons other than their excellent sword/knife & other hand weapons.
It was not just steel/metal that was collected but wood also.
My dad had his solid plaster factory & trucks confiscated, the factory ( third biggest in Brisbane) was used to make soda(soft drinks) for the US guys stationed here.
They created the "Brisbane line" of defence and US personnel were stationed in and around the city. My father and his brother were allowed to keep a truck each if they went to" the Terrirory" to build a road through the centre south from Darwin. They were not accepted into the forces as they were "C Class". They had flat feet & considered not able to march, when they tried to enlist, so deemed to be unfit for service=C Class. The Japanese did indeed bomb Darwin but the road for supplies was never needed for the purpose of slowing the advance of the attackers. All of my dads mail to Mum (newly weds) was scrutionised and much of the letters cut out probably more to do with morale back home than sucurity.
I kind of think the road could have had the reverse affect if the enemy landed though there would have been a plan to destroy at least some in that event.