China can coerce it's diaspora through their family ties and social circle back home[1]. That isn't normal and is very difficult to pull off in democratic countries.
There are sufficient “loopholes” that would allow Western democracies to do this. The only difference is that China is forthright about what it does & is willing to do.
Look at the Assange fiasco for example, or Guantanamo Bay, or the use of rendition to allied states by the CIA, or sitting in on torture conducted by allies (recently in Yemen), etc.
Not to mention the complete disregard of international law when it comes to Israel, and in the same, hypocritical breath, repeatedly insisting that the Russians must follow international law (which they should).
Unequivocally supporting and providing complete material support for a country that has been accused (or investigated for) of genocide by credible sources (MSF, ICJ) comes pretty close. Especially when most of the bombs used for said genocide were provided willingly by the US, knowing that it will be used to level a city to the ground.
Not really, for most countries this kind of intelligence gathering is really expensive with low ROI and so not worth it. (Edit: word order for clarity.)
The typical country is closer to Cambodia or Honduras not a world power. China can leverage it, but most countries aren’t China.
Intelligence is only worth what you can leverage it for. Knowing a stock is going up tomorrow by 5% isn’t worth much for most people, but it’s worth a far more to someone who can toss 100m into it.
America has a vast economy, huge military R&D spending, massive foreign entanglements etc, and it’s arguable if the CIA is worth its budget. I’m not arguing it should be defunded, but there’s been significant debate even within the intelligence community around the topic for a bunch of different reasons.
Scale that down to a developing country with 10 million people and human intelligence gathering within foreign countries is almost guaranteed to be a waste of time and money.
Emigrants always have ties to the originland.