Because of the Crises in the Age of Calm(a misnomer by itself, relatively true in light of the more recent Ages), all of the world either degenerated, advanced, maintained, or stagnated technologically and culturally, among other things. Additionally, for some reason, dimensional rifts intersect the home dimension frequently. This has resulted in some nations relying on magic and others performing massive space travel and others bringing in alternate laws of physics with their lands.
The most ancient of technologies seem to be medieval in nature, most of them coupled with magic, to compete with the more modern and advanced technological societies. Due to some law of nature arising from magic, creatures such as unicorns and dragons inhabit these nations. The lands of Sho-rock, Silveria, the Shadowlands, former Esmarga, and the Darian Isles/Hispania fit this category in varying degrees. The overabundance of magic has created the Ancient and Haven Dimensions, one with no magic and high magic, respectively.
The lands of Erronithia, Thoristan, Jael Gath, Dawesominia, Romania, Trentopolis, and Gondor, among others, are more or less modern or near-futuristic. They are able to send spacecraft, but some choose not to. Conventional warfare still abounds, with tanks, missiles, artillery, amphibious assaults, airstrikes, and whatnot. Biological warfare seems to have been the favorite in the early War because of the abolishment of the Geneva Convention. Due to the dimensional rifts, Erronithia has acquired use of practical wormhole technology, as the universe's physics have been scrambled to allow it. The League of UN mainly uses Cold War and the War on Terrorism technology and techniques in their peacekeeping missions(which are rare). The Tank Dimension split in an almost unrelated way, but it seems it was influenced by the nuclear bombs redirecting the metaenergy lines on Earth.
Those humans that have fled Earth and some alien races have come back to bring in their futuristic technology to fight the World War. For some reason, any threat to Earth itself being blown up is shifted by a dimensional rift, thus the War continues on Earth, even though Earth is destroyed in one dimension. This is an interesting phenomenon, some say it is by design. Others say its just that the nations are extremely lucky they are in the dimension in which Earth always survives. This was first experienced when Endor uses a Death Star to destroy the planet. Schinaam of Luminne, the High Rahn Empire, Majestic Dawn, Cayorria, and others are space faring people. The Kombat and Space Dimensions were created due to the burden placed on the spacetime continuum, causing it to snap.
The land of Neo Samosa is advanced enough to put a spacecraft into space, but does not prefer to(although the space military branch of Neo Samosa, the Final Frontier, does). It seems to be an amalgamation of many different technologies throughout the ages. Neo Samosa largely uses steam and chronodisplacement(time travel) technologies. It is in the process of studying the phenomenon of the Dimensional Rifts. In colonizes any dimensions that is found, under variying names, as a ministry of the Chronocratic Guild.
The technology of the Idiosyncratic Igloo, the Bentonian Koalas, the Kingdom of Nowhere, and the Land of Stewardship is unknown or minimal, due to their small size. The Koalas seem to be barbarian in nature, due to them being animals. The Kingdom of Nowhere are guerilla warriors, and it is conjectured they have WW2-Cold War era weaponry. The Land of Stewardship is known to possess some of the most advanced stock market and banking software, but the extent of their other technologies are unknown. The Idiosyncratic Igloo seem to be a fishing people off the coast of Florida or Antarctica, and are peaceful. The rule of War stays true: nations at war advance in technology the most.
There is only one group who has melded both highly advanced technology and magic seamlessly. Their name must not be uttered! Many psychic and mind control technologies are owned by this group, and has infiltrated all of the Nations. Their knowledge has been given to them from below. From WAY below, the recesses of human imagination, the Void, and the Abyss, and who-knows-where-else. They have strongholds in space and other dimensions.
Interestingly, all Nations use one form of a nuclear bomb. It seems it is the only universal technology everyone possesses for sure. Those Nations steeped in ancient ways do not prefer to use them, but it is not unheard of. Thus, WW3 is dominated by nuclear warfare, or the fear of it.