"thoughtless action" is a correct and usable phrase in written English.
You can use it to refer to an action that was done without any consideration or regard for the potential consequences. For example: "His thoughtless action caused a great deal of damage."
It takes just a thoughtless action to lose it and the sweat of thousands to rebuild it," said Kaspar Villiger, the chairman, according to Bloomberg News.
The rail minister, Paul Maynard, said of the strike: "This is yet another unnecessary and thoughtless action by the RMT, who simply do not care about the travelling public.
Another thoughtless action is also inspired by my classmate: when people have a luggage or bag while sitting in a moving vehicle, they want to free their hands to do other things, while at the same time, they want to hold their belongings.
I enjoyed the article "Tigers and Dinosaurs" (feature, Nov. 13), although it brought back painful memories of the shortsighted decision by the administration in 2000 to evacuate the Guyot Hall museum in order to "make way for office space". To an institution like Princeton, history counts for much, and much history was destroyed by that thoughtless action.
I sincerely and unreservedly apologise to all First Nations people for this thoughtless action".
Ivanka's clapping was refined and engaged, while Kushner's applause looked obligatory, a thoughtless action he had to engage in while in the midst of a daydream.
I came across a few thoughtless actions inspired by my MIMS classmates.
If the opposition shows rash and thoughtless actions out of joy of victory, Koreans will never forgive them".
By shooting a friend and hunting partner while hunting birds in Texas, Vice President Dick Cheney has embarrassed hunters and shotgun owners by his thoughtless actions.
After the video was published by the Sun last month, Smith apologised for his behaviour saying he was "deeply sorry" for causing "deep offence with my thoughtless actions".
He regarded the bloody outrages of the Nazis and their predecessors as the thoughtless actions of unbalanced minds; he was unable to comprehend the nature of National Socialism and remained powerless to prevent its seizure of power.
