All the globe's trouble spots are in areas that have very poor to no border control. Look at a map - there's no way to prevent the flow of arms, people, etc, which is why central government forces cannot control the territory. So, since government really doesn't exist, it takes a foreign power like the US - and UK, France, Russia and Turkey before us to impose order. As such, there's also no blow-back from any offended parties (other than the terrorists) because there's no there, there.
MX, OTOH, is just like a narrower version of the US. In fact, their southern border is extremely easy to police. So, regardless of what people may imagine MX to be like, it really is a functioning, centrally controlled government. Just a crazy, wild west corrupt version, but certainly operating in control.
The **problem** is, however, that the functioning MX government and economy is based on the drug trade. So the issue is economic, not religious, not anti-colonial, not any of the list of traditional 3rd world grievances, but rather simply the question of: what will Mexicans do to earn a living if the drug trade is impacted?
Get it? The challenge for Trump et al is to figure out a way for MX to transition its economy away from easy money drugs to something a little more substantial. And that, to anyone who's ever been down there and comes back with the same question, is: why isn't MX developing it's vast treasure trove of beautiful real estate? And the answer is prohibitive rules & regs, including laws against non MX citizens from owning coastal real estate.
Fix that, and who would waste time plying the drug trade when there would be vast $trillions to be made developing vacation/residential haciendas for the billions of Chinese, Indians, etc that would rush the country?
Yeah, that’s the ticket. Convince Mexicans that the best way to end drug violence is to sell off large areas of their country to foreigners. I’m sure they’ll jump all over that plan.