Turns out it'd be a dissapointingly small sphere:

US annual defence budget = $800 billion

2% = $16 billion

Obsidian cost per kg = $5

Total kg in budget = 3.2 billion kg

Density of obsidian = 2.6 g/cm3 = 2600 kg/m3

Total volume of sphere = 3.2b/2600 = 1230769 m3

Volume of sphere = 4/3 π r^3

Radius = (3V/4π)^(1/3) = 66.48 m

The sphere would only stand at 133m tall, I propose we instead utilise the entire defence budget for a much more skyscraper like 490m tall orb

It would also crack instantly. Obsidian's not durable.

My only question is why we didn't build the orb back in the Eisenhower administration when it was most needed.

Would be a far better use of the 'defense' budget than what they're currently spending it on.

Thats funny because more than 2%, more like 40%, of our defense budget is going into a black orb never to be seen again and is completely unaccounted for.

2b2t players:

I support this project.

Just imagine the size we could build if we used all of the defense budget. It's resonant frequency would blow the eardrums of everyone on the West Coast and kill all marine life. One day when I'm presadent...

Why would it hum and am I taking this too seriously?

Why does the government keep this from us?
Why are they so afraid of giving the public what they deserve and want, an ominously humming obsidian sphere?
What if China builds a mysteriously vibrating marble sphere first?
Were all the plans for this project taken to Mar-a-Lago? Or saved on Hunter Biden's laptop? Or hidden in some pizza restaurant?
Just asking questions...

Something one might propose to build in Night Vale.

And eventually someone will spray graffiti really high up somehow

In 2022, the defense dept spent 590billion dollars, 2% of that would be 11.8 billion dollars. While it is impossible to calculate the cost of constructing this sphere, it cost 25 billion dollars to develop the Airbus A380, and 150 Billion to complete the International space station.

The US defense budget isn't an infinite pool of money. It's 15% of the federal budget. It's dwarfed by healthcare spending (27%), and Social Security (24%). I'm not a war hawk, I try to bring this up in lefty spaces because skimming off the defense budget to solve social problems is a common, and silly belief.

https://en.wikipedia.org/wiki/United_States_federal_budget#Major_expenditure_categories

What percentage needs to be cut for it to float in the air and shoot death rays at heretics?

Hell yeah, ominous hum!