WW2 saw Australia design a cruiser tank called the Sentinel. It was a particularly good tank designed specifically to engage with Panzers but it's arguably not a truly Australian design. The M3 Lee was used as a design base and a British tank engineer was sent to Australia to compensate Australia's lack of experience. After two years in the designing stage the Sentinel saw considerable changes as attempts were made to keep up with the pace of German engineering - in the end it began to resemble an American tank more than a unique Australian design.

By 1943 the M4 Sherman was now the mainstay of American armour and the sleeping giant had mass produced hundreds to support the American deployment out of Australia (which was being used as a staging ground). In consideration of this the project was terminated and the money was instead put towards building railways to support logistics and deployment of the M4. In the end the only action the Sentinel ever saw was in cinema.