It has been pointed out, with underscores, that she "accepts" rather than "supports" the US bombing of Syria, and that puts her out of step with other leaders gathered in London this week. Oh dear, a national leader who doesn't relish killing people ... how terribly squeamish.
But hang on ...
On Thursday, Robert Fisk of the Independent reported from Douma, the city where the Syrian chemical attacks that prompted the US retaliation are said to have occurred.
Fisk travelled the pummelled city freely — most of the fighters and government minders from Bashar al-Assad's regime have got out. His report casts serious doubt on whether there actually was a chemical attack.
Fisk has lived in and reported from the Middle East for 40 years; he is fluent in the languages and has never been tainted by suggestions of political partiality or propaganda. In short, he is the genuine article — a journalist.
The United States has said al-Assad used chemical weapons in Douma, and maybe that is correct.
But it should be remembered that for more than 50 years US foreign affairs have featured two constants — putting its troops in other people's countries and lying.
Vietnam, Cambodia, Laos, Grenada, Afghanistan, Iraq ... all have been marked by a consistent policy of lying to the American people and the world.
So perhaps Ms Ardern has good reason to be cautious.