It looks like there were... but obviously dramatically reduced in number. The US probably has this many in a fortnight now... so it's hard to say how much desperation or social responsibility play into this.
https://en.wikipedia.org/wiki/List_of_mass_shootings_in_the_United_States
I do think the school shootings in the US is from socially maladjusted young men (with likely mental health issues) getting access to assault weapons... whereas the machete attacks in Australia is more likely motivated by gang activity (drugs, money, etc) which are less likely to exist without people feeling desperate.