Here is the transcript of Trump's "terrorist attack" in Sweden comment:
The references to Nice, Brussels and Paris make it clear he's talking - primarily - about Islamist terror attacks. He adds Sweden to this list, and specifically says "look at what's happening...last night". Now never mind the nonsensical grammar; the ploy is clearly aimed at planting the idea in people's heads that Sweden is the latest (European) target of a significant Islamist atrocity. Because there
had been a major attack the previous day - but in Pakistan, not Sweden.
Now this is all classic Trump, because he has left himself
just enough wiggle room to be able, sort-of-plausibly, to later say "I wasn't talking about a terrorist attack, just general crime and inter-cultural tension". (Leaving aside the obvious fact that "general" levels of any cultural phenomenon are observed over a period of months or years, rather than happening on a particular day.) In much the same way that he didn't explicitly say "If you value your guns, then please assassinate Hillary Clinton" - while at the same time dog-whistling that very message to his supporters. It's all nudge-nudge-wink-wink - the sort of nudges clearly intended to make you spill your drink on yourself, while just casual enough that he can say "Oh sorry mate, accident" with a semi-smirk on his face as he says it.