1: Go to Documents\My Games\ICBM-Escalation\SAVES\SAVE(x)
2: Open world.txt
3: Find the desired faction(s)
4: Edit ScienceBoost, ProductionBoost, and/or EspionageBoost
5: Profit!

Self-explanatory.

Open File Manager and go to Documents\My Games\ICBM-Escalation\SAVES

The number of your newest save depends on how many saves you already have. Assuming you have no other saves, it'll always be SAVE1. If you have three other saves, then the new save will be SAVE4, and etc.
Open the save folder we want to edit.
And open world.txt.

There's a bunch of stuff in here, like match settings, state of the game, number of units on the map and their positions, and more. The longer the game goes on, the more lines there are that keeps track of it all.

Assuming we're Player 1, then we want to find the stats for North America. Simply scroll down a bit.
And there it is! Under this faction's stats, which also keeps track of technologies unlocked, units in stockpile, units deployed, and more, is what we want; ScienceBoost, ProductionBoost, and EspionageBoost.
(I'm not sure why they're 0.99999 as of 1.0.0, but they do return as 100% in-game. It was 1.00000 in the original game, too. So just imagine it as 1.00000, I suppose. )

Here, we can just edit the values to our heart's content! Let's give ourselves 400% faster research speed and 50% slower construction speed.
Save the file, and load the modded save in-game.

We can pretty much mess with and edit every other other faction in the game. Although we can manually scroll down the text file to find them, it's faster to use the search function provided by the text editor.
If we want to find Russia, tap CTRL+F and type in Player "Russia" (or a shortened version)

If you want to quickly edit global GDP across the board without having to do each faction manually, tap CTRL+H and use the replace function:

Here, we gave every AI a 50% production boost for a harder difficulty. Ah yes, the bread and butter of every strategy game indeed; just giving the AI buffs instead of making it smarter.

- Works in campaign missions.
- Editing a save file mid-match is possible.
- Work in the original ICBM.

I do not condone cheating in multiplayer (not that this method should possible in MP anyway) but singleplayer cheating is absolutely harmless and just for fun. Clearly the developer also allows it, since they would've just encrypted the save files otherwise.

Maybe you don't like strategy games and don't want to 'git gud', and just want a 'funny haha' power fantasy war game where you get to destroy everyone else with little resistance. Maybe you want to create your own scenarios with realistic GDPs. Maybe you want push yourself and fight-off vast swarms of AI armies with limited resources.

At the end of the day, you bought the game and it's up to you how you want to have fun with it. I made this quick guide to show that you can, in fact, do just this.

The AI, depending on its personality, has lists of units that it prioritizes and attempts to build in order. However, these lists are finite, and when it reaches the end of them, it simply won't build more. If one plays around with very high production rates for them, they'll probably run into this cap very quickly.

I actually already modified the correct file and copy pasted the end of the lists 2-4 times over for myself. It's a bit tacky but it works. The 'essential' unit lists are untouched, meaning that the AI will still build the same way early-game, but when it has excess production, it'll now be far more willing to spam 'luxury' units.

Here it is in action with instant production and research.
Blue alone has about 40 spy, laser, hunter-killer, and kinetic satellites combined, as well as 20 missile silos

I've seen a guy on the forums asking if there's a way to raise the unit cap, and I was like, yeah, there's probably more people who want to lag the hell out of their game as well and make it as unbalanced as possible as well. So I figured I'd paste my modded file for y'all.

I'mma come clean. I'm not a full-blown modder so I can't figure out how to use the modding tools and upload to the workshop. Plus, it's just a single text file, right? ;)
Installation:
1: Navigate to the AI folder and open StrategyConquest.txt as shown below.
2. Create a backup file as the game won't let you join multiplayer with tampered files. (or just verify file integrity later)
3. Open https://pastebin.com/raw/x9Za8abi
4. Copy everything (CTRL+A) and replace the vanilla text with the new one.
5. Done!

Note: This does not make the AI smarter. It does what it's called. If you're willing to learn how the text file works yourself, you can also modify the AI build order, limits and strategies.