I think it's on imports from anywhere, though, not only Australia. The UK is another country that exports a lot of pharmaceuticals to the USA, so could be hit in the same way.
Remember though that the manufacturer and exporting nation do not pay the tariff - the importing end customer pays that. The manufacturer loses by reduced export sales. I am not sure Mr. Trump comprehends that, because when he talks about imposing tariffs he implies the tax is on countries and they pay the tax.
President Trump seems to imagine manufacturers can set up lots of new factories overnight! He also appears to imagine exports and imports are only of physical goods, both manufactured items and raw materials. Or perhaps he does mean only physical imports.
Yet there is also an enormous international trade in intangibles like the arts and sports, public-service TV and radio programmes, transport, business consultancy, insurance, scientific, medical and engineering knowledge, high-level education. Are they subject to import taxes in the USA?
Even many manufactured goods are not as clear-cut as seems, because certain classes involve a labrynth of international trade in the paths from raw materials via components to finished items.
Whether this new tariff on imported medicines is some sort of revenge for Australia (and perhaps other countries too) not toeing the Trump line, probably only Mr. Trump can say. Nevertheless his aim has always been to make the USA more self-reliant, even rather isolated - ironically after a century of her own international corporate-raiding, political domination and cultural hegemony. Unfortunately he shows little care for, and indeed may not understand, the consequences of his actions for other nations.
