So in one year, would the world have agreed to make one solidified dollar/euro/whatever, will each nation still have an individual leader, or will there still be multiple.
I'd very much doubt a year would be enough for a global unified currency, whatever the scale of disaster, or to drastically alter the political landscape of more than a handful of nations - unless the aliens have for some reason very specifically targeted particular established political interests, and it would take a lot of work to make me believe in aliens showing up on that time scale and getting both the understanding of human politics and the motivation to hack human power structures rather than smashing them. (I think you'd also need a bit more of the alien psychology worked out with regard to precisely how they see territory and ownership and so forth; it would break my suspension of disbelief for them to be exactly like humans in this regard, and the interesting areas would be where they have fundamental conceptual differences.)
I guess I'm just unsure of how much change can take place over the course of one year, and how much of that change I need my character, who as of now will be around 17 and in high school, to communicate about to the reader
I think the fundamental question there is, what's your character like ? And the underlying fundamental point;
description is character.
On one hand, I can imagine doing this from the POV of a geeky kid who is fascinated by the aliens and who is very much focused on what we know about them - quite possibly to an extent that surrounding people find suspicious and that has to be hidden. Or from the POV of someone who very closely identified with their home and community, who has felt that be broken, and who is very aware of all the ways things are different now and very focused on the details. (It would be hard not to make that a bit too angsty for my tastes, I think.) Or from the POV of a jock who doesn't really care too much care about any of that stuff so long as there's getting to blow aliens up, and who maybe still thinks of that too much in terms of having played
Halo or
Mass Effect or whatever seventeen-year-olds play these days (I am 39 and I play Civ, so no research help there) which would mean having to get the information across to the reader despite the viewpoint rather than because of it. (If I were doing that - which I almost certainly wouldn't, jock is not a mindset I grok - I'd be very tempted to include background details in briefing notes as a chapter-header sort of thing, and have the jock not pay adequate attention to them and get in trouble thereby.)
Also, if the story is first-person, you have the consideration of who the character is writing it for in the fictional universe, and what the character expects
that reader to know. If the character is writing for a time capsule that's going to be shoved into the ruins in the hope humanity will recover in years to come, that might be reason to explain rather a lot, for example.
(One of the nicer things about the SF mystery I am currently working on is having a first-person security-professional protagonist who every now and then stops to say "I can't actually explain how this bit works, that's still classified." I figure that would be obnoxious if anything plot-important relied on it, but it's helping me be clear on what sorts of information she can talk about and what her attitude to security is, world-building and character development both - and she very much assumes her in-universe reader has seen the in-universe equivalent of
Die Hard and
Lethal Weapon but has no experience with real security work.)
