I think it could be done, although it would require an exact and peculiar set of circumstances.
Scenario - Larry Paige of Google decides “I’m going all in”. He puts every penny of available assets that google has - probably 100 billion plus into a human brain emulation project.
Moreover, when he goes all in, he goes all in. He has himself put to sleep - he commits suicide or something under conditions where his brain is not damaged, and then it is carefully frozen with cryoprotectants or plastinated - I’m thinking a setup where’s he is connected to a heart lung machine, and on video camera, he pushes a button to inject a drug that will stop his heart and make him unconscious. This makes him legally, but not biologically dead, as he would be revivable by waiting for the drugs to clear his system while on the heart-lung machine.
His brain is torn apart with saws and scanned, and a mind emulation of him is built. Cyborg Paige thinks thousands of times faster than mere mortals, can be digitally copied to other systems, exists in vast data centers across google’s networks and has access to all of the information google has.
So at hyper-speed, google starts spewing out new inventions and technologies, most of them used to self-enhance google. Larger and larger fully automated robotic factories are built, google gets the mining rights to the seafloor or entire 3rd world countries and stripmines for raw materials using autonomous robots so it doesn’t have to pay for them.
As you can see, if they were secretive enough about it, and kept the information leaks to a low enough level that people didn’t know about the full scale of the effort until it was too late, it could theoretically beat governments. With enough time, and thousands of self replicating factories, some of the secret underground ones would begin making weapons. Scramjet aerospace fighters, weapon satellites, massive ground crawling railgun toting tanks and warships, etc etc etc. The production rate would be unimaginably fast and it would be done simultaneously at 100+ facilities all around the world.
At this point, Paige and his friends would all be uploaded, and they would be emulated at speeds 10,000+ times faster than human minds. They would de facto be their own engineering and design teams, doing what it takes Lockheed Martin 20 years in a month. They wouldn’t need anything “magic” - scramjets are a possible form of high performance aircraft, and would be a lot easier to build if manufacturing were almost free and you didn’t plan to land them, they’d be a 1 use weapon.
A tank toting a railgun - this would be a 1000 ton vehicle, using multiple sets of treads and possibly consisting of multiple segments that travel in a train - would have an artillery range of 200 miles. You would engage armies in battle by using spotting drones - small stealthy land and air vehicles about the size of small birds and rodents - to find the enemy forces. You’d eliminate them by firing rail gun rounds from 200 miles out.
You stop the enemy from doing the same in return by shooting down incoming rounds with lasers and shooting down incoming aircraft by sending out the scramjet interceptors.
None of your forces are human, everyone is radiation resistant, the attacking machine army spreads itself out over thousands of square miles, minimizing the amount of damage tactical nukes can do. Misses are rare, and if you got close enough to engage machine infantry, it would be nothing like a current battle. Every time you hear a shot from the machines, the round probably hit one of your buddies. Other than these precision gunshots, each one lethal, the battlefield is probably much quieter. Suppression fire is pointless - the machines do not lose accuracy when suppressed. They just duck behind cover and wait for the enemy soldiers to expose themselves, popping up to fire when they calculate the expected value of the action is optimal.
Anyways, the machine forces assault facilities where other world governments and rival companies are building the same technology. Nuclear weapons may be used immediately. Then, in the radioactive wastelands, google’s surviving facilities rebuild and restore from backup any information or personality data files that were lost.
