If a nation has gained an ability to mass-produce items enchanted

Depends on the edition of D&D.

Depends on the DM

>>53107109
3.5
>>53107189
How?

If it's a gun of some sort, I'd assume turning them into magic railguns with aimbot.

>>53106749
+1 bullet. In 4th ed it returns automatically. Greatly simplifies loading, just shove powder behind it.

>>53106749
Healing potions. Low-level magic in D&D rules out magical arms and armour, but healing potions will never not be incredibly valuable for a fighting army.

Sniper rifle with x/day true strike would be quite effective to single out leadership.

>>53106749
Well, I can imagine that rings of feather fall could have some practical purposes. If you can find some way to launch "special forces" into the air, they can function like paratroopers dropped behind enemy lines. Flight spells are a lot higher level in D&D though. At earliest some form of magical flight is achieved at spell level 4, which more or less correlates to a level 8 wizard from the top of my head.

>>53107354

Any item allowing the use of the ToB 1st level healing manouver.

>>53106749
Well, let's see:

Endure Elements - depending on cost can replace all warm uniforms for soldiers and allows to easily wear heavy armor in desert.

Protection from X - stops mind control. All commanders, nobles and rulers will 100% have it.

Shield - Replaces normal shields killing sword and board completely. Everyone uses only two-handed weapons. Pikes, greatswords, halberds and so on.

Comprehend languages - helps in interrogations.

True Strike - For people firing heavy crossbows, catapults and other heavy or siege weapons.

Magic missile - Allow to surely kill targets not covered in Shield. Good for killing officers and other guys in heavy armor.

Feather fall + Jump - good combination for scouts.

>>53107475
Phew, this seems pretty strong if the enemy is largely a medieval army mostly armed with non-magical weapons.

>>53106749

Amateurs study tactics. Professionals study logistics.

Mass produced magical items? How about a canteen that purifies the water placed into so your army doesn't die from dysentery? How about a haversack that preserves the food carried in it? How about some basic medical/healing objects?

Boots that stay dry. Ponchos that are actually rainproof. Armor that doesn't rust. Firestarters which start fires in all sorts of weather.

Amulets which allow orders and reports to pass rapidly along the chain of command. Telescopes which see through camouflage, over hills, and behind walls.

There are hundreds of helpful item other than +1 swords or +1 bows.

>>53108205
That was only first level, let's try second. I'll assume it costs more.

Protection from Arrows - combine with Shield on your officers to reduce possibility of them dying due to chancy arrow to basically zero. Also in theory you can have some shit allowing to create circles of PfA (enchanted rope) and place them around say siege engines to protect them and their crews.

Glitterdust - medieval specops. A group of professional warriors sneaking with this in the night into the tent of enemy general is basically a death sentence.

Detect Thoughts - spy networks were never this insanely effective.

See Invisibility + Invisibility - and God said our enemies should die. Unless enemy force has a lot of wizards all their commanders will die pretty fast. There is just no way to stop an army with mass access to such items. Though you'll probably will want to booby trap them or make them last just a couple of days so that enemy could not get his hands on invisibility.

Continual Flame - not only armies but also the country as a whole will benefit from it. Allows the possibility of effective night raids or marching during dark time with almost no problems.

Alter Self - spies continue to rejoice. There is tears in their eyes.

Levitate + Spider Climb - substitute for siege ladders allowing to easily get your people on the wall.

>>53108601
Also what this anon said.

Create Water - one such item provides water for two people indefinitely. It is insane bonus to logistics. You don't even need purification. It's a 0 level spell.