Another factor is the domestic supply deficit in the US. Do we really have the same deficit here?
Australia is post-peak in terms of oil production and relies increasingly heavily on imports to meet domestic demand. We were never a significant oil net exporter, but did achieve production rates close to consumption for some years.
The well known Bass Strait field peaked in 1985 and is all but gone now, with production a fraction of what it once was. Nationally, production peaked around 2000.
Gas on the other hand is a far less depleted resource in Australia and production is still rising. Depending on what estimates you use, somewhere around 85% of it is still in the ground. That said, Cooper Basin (SA) reserves are substantially depleted and production in decline. Bass Strait reserves have also been significantly consumed although production is not presently constrained by the size of remaining reserves.
Most of Australia's gas reserves are in WA, NT and coal seam gas in Qld and NSW. Tasmania is the only state with no local gas production industry, although the Yolla field is half way between Vic and Tas (production is piped to Vic) and it is probable that small amouts of coal seam gas could be recovered. Every other state has at least some gas industry either conventional or coal seam (although gas production in NSW is relatively trivial, most supply to that state coming from SA and Vic).
So in short, it always makes sense to look for and extract oil since there is a market locally and internationally. But in Australia, it only makes sense to develop more gas if you're planning to export it (which needs to be large scale to be economic) or, on a very small scale, supply nearby towns or a mine that otherwise don't have access to gas. Australian domestic gas prices are low by international standards due to the local supply situation and the relatively high cost of liquefaction for export.