We'll be curious to see what Cliff has to say. It does have the broken line of interrogatum, but we would expect that line to be thicker. This has the thinner line of resolutum. We would also expect interrogatum to have significantly more blue on abdominal segments 3 and 7. Segments 3 and 7 in this image look more like resolutum. Is there another Coenagrion in Alaska that's in between these two species?!!

Quoting Dennis Paulson's Alaska Key:
Thorax often with greenish tinge, no black markings beneath it; pale stripes on top of thorax undivided (divided in small proportion of individuals); no blue on abdominal segment 7...Coenagrion resolutum (Taiga Bluet)
Thorax intense blue, with conspicuous black markings beneath; pale stripes on top of thorax divided (like exclamation marks); blue at abdomen tip extends onto segment 7...Coenagrion interrogatum (Subarctic Bluet)

Not sure where the color falls, but that's probably better left to someone less colorblind. Only mark that goes to interrogatum is the broken stripe, which is apparently not definitive. I was puzzled a bit by the mismatched s3, should have looked a bit more carefully at the references.

I'd lean more towards C. resolutum due to the black/blue colouration. The patern on Segment 2 dosen't look to be broken and segment three is half black (rather than less than a quarter black in C. interrogatum). I'm using Ed Lams (1) book but don't have much personal experience with these species yet.