BASICS: Military Guide

Spies
The Basics:
 * You can spy on any nation you're at war with or that's in your war declaration range, twice a day, plus one extra for each war you're in.
 * Full spies (either 550 or 800, the latter with the CIA) should be maintained at 5k+ infra. Before then you should be purchasing them steadily (especially if getting randomly spied on) as long as it doesn't hurt your warchest.
 * An edge in spying during times of war can be very beneficial to protecting your nation and inflicting the most damage possible. During times of war, when coordinating, the nation with the highest odds on a target should be doing the spying. Do not waste your money doing spy operations with low odds (anything lower than 50%) unless you have a large warchest.

Worthy Operations:

The following operations are most meaningful early on in conflict, to neutralize the enemy:
 * Gather Intelligence - Conduct this operation at the outset of war (so you know what to expect from the enemy, mainly in terms of what their warchest is, and consequently how to best fight them) or before raiding.
 * Change DEFCON - Conduct this operation if your opponent is at DEFCON 1 (to increase your odds on ground attacks).
 * Change Threat Level - Conduct this operation to reduce the enemy's spy odds (conduct it early on if you plan on frequently spying).
 * Destroy Nuclear Weapons - Conduct this operation if your opponent has nukes (to whittle away at their stockpiles and decrease the punch they pack).

The following operations are most meaningful later on in conflict, once the enemy is neutralized, to inflict as much damage upon them as possible:
 * Destroy Money - Conduct this operation until it destroys $2-$3 million or less or until the cost is more than the return. It's important to reduce the enemy's warchest and this is the best way to do that.
 * Sabotage IRS - Conduct this operation to reduce their collections (all the way down to 23%).
 * Incite Government Propaganda - Conduct this operation, when the enemy is in anarchy, to force them to collect (in anarchy) before being able to change government type.
 * Assassinate Spies - Once Destroy Money is returning $2 million or less, spies are a better return (20 spies assassinated amounts to $2 million destroyed).
 * Assassinate Generals - Consider this operation higher priority if you have weak generals and the enemy strong ones or if the enemy is actively assassinating your own generals.

Any other operations aren't worth the reward so should be avoided. Once you've exhausted the above operations and once the returns are low move on.

Airforce
The golden rule regarding airforce usage during times of war is to ONLY keep on hand and attack with 9 in strength in bombers (one level 9 bomber or enough weaker bombers of a combined strength of 9 or more). The remainder of your airforce should be the strongest possible fighters.

Navy
The Recommended Navy Order:
 * Max Carriers
 * Max Cruisers
 * Max Destroyers
 * Max Frigates
 * Max Submarines
 * Max Landing Ships
 * Max Battleships
 * Max Corvettes

Keep in mind that you should be maintaining a navy at 7k+ infrastructure since you'll have access to all needed improvement slots. Below 7k infra, where you don't, you shouldn't be carrying much during times of peace (the first few ships, at most).

The End Goal:

During times of war you want to reduce the enemy's navy to 0 so that you can battle support and blockade them (battle support takes precedence out of the two). Keep in mind that you can't battle support and blockade at the same time, and that if you do either of the two you lose the rest of your navy actions for that day.

Generals
The golden rule regarding generals is that you should be replacing them as little as possible (since terminating them returns only 70% of that general's XP). Unless you're at war and you could really use the boost you should be saving for good, if not the best, generals.

When declaring war be sure you never disable XP.