1. Its geography means it's impervious to conventional invasions.
2. Its embracing culture will attract more immigrants.
3. It is an offshoot of western civilization and therefore has natural allies in Europe.
China's advantages are:
1. It has a population that is 3-4 times the size of the US.
2. Its economy is still underdeveloped, therefore economic growth is a lot easier.
China is interesting in that its society is rapidly aging before it becomes a high income country, which is enough of a rough transition for high income countries.
You'd have to be insane to invade China, though. "Never get involved in a land war in Asia". Especially never get involved in a land war in Asia against someone with an army the size of China's.
> 2. Its embracing culture will attract more immigrants.
This advantage the current administration seems to be working as hard as possible to destroy. As far as I know, though, this is still an advantage for the US compared to China.
> 2. Its [China's] economy is still underdeveloped, therefore economic growth is a lot easier.
It's not nearly as underdeveloped as it used to be. Further growth will be significantly harder than past growth was. Can China keep it going? I don't know.
As to the economy, as long as China grows faster than 3%, it will gain relatively to the US.
Also, weaponize space and all terrestrial advantages become mostly moot (no GPS, communications, etc.).
Maintaining that deterrence is the the actual disadvantage to China - not the risk of invasion, but the cost of preventing invasion.
Battles are rapidly migrating to the air (drones, missiles, etc.) and cyberspace.
You don't need to invade the entire land, you just need to bomb a few targets. A nice chunk of China's population and structure is distributed across China's shores. If you take a look at photos of China at night from space, you'll see that the shores are way way brighter than inland. Interesting enough, there are plenty US allies nearby which could be used as base to make bombing easier.
Edit:However, I, personally, don't think we'll see big dogs such as U.S and China fighting in any moment near future. We have developed tools so efficient to kill each other that the best ideia possible is to not use them. At these times, big wars are too costly for everyone, involved or not.
1 party rule can make quick, bold changes for better or for worse.
In the US, we're stuck with slower change again for better or worse.
Pro.1 does also apply to China I would think.
I'm not sure con.1 is that much of an advantage. other than a larger national market.