But, if neither side wants it to be an act of war, it's de facto not.
The notion of an "act of war" is largely a pragmatic political tool. To the extent that they exist legally, they're invoked so haphazardly and selectively by e.g. the UN that it would be difficult to justify regarding the rules about "legal" and "illegal" war justifications as, per se, any kind of definitive guide for declaring what is and is not a "real" act of war.
Which means we're left with "both sides say it's not, so... it's not".
[EDIT] To be clear, if one or the other had chosen to regard this as an act of war, there may be room to debate the truth and justice of that position, or how we might interpret that stance based on international law and precedent—but neither (apparently) did, so it's rather moot. Yes, it probably could be so-regarded with some justification. Yes, there'd be room to, not without reason or basis, counter that a war asset providing intelligence to an adversary in a war is already engaged in war, regardless of who's operating it, et c., et c. It joins dozens of other actions as kind-of unrealized "acts of war".
But if this were a manned aircraft, that would be a major thing. The question is, what's the important element here.
It isn't necessarily the killing, if a plane were shot down, and the pilot ejected without harm it would still be a major thing, so there must be some element of, attacking a foreign nations military hardware is a no-no. But then the rhetoric doesn't seem to match that.
Hopefully the RF will think twice before similarly harrassing an American pilot, which would be much closer to, if not crossing, that line.
Russia is at war with Ukraine and receives intelligence from US and UK 24/7 that surveillance aircraft is not there defending the coasts of Turkey or Romania.
This was in international waters. The drone had every right to be there.
Just that it seems far fetched that downing a surveillance drone is an act of war.
It's an obvious provocation, and it's absolutely not in the US (or NATO's) interest to be drawn in in this manner and time. So instead you get this passive-aggressive shit talk.
Good news is that incidents like this will increase US military support for Ukraine.
>Several times before the collision, the Su-27s dumped fuel on and flew in front of the MQ-9 in a reckless, environmentally unsound and unprofessional manner.
That seems more intentional than a simple fly-by anyway.