Obviously not a biologist, but if you could target a specific protein on the bacterial surface it might work. Alternatively you could CRISPR some human cells that generate the bacteria-killing RNA constantly.
Yes, that would be super cool. But also crazy-risky!! :)
But the risk is not due to chance, its due to the unknowns. Once they're no longer unknowns we'll be able to engineer such a therapy.
Alternatively, once we understand our biology so well, we might as well just patch all the "bugs" so that we don't get infected by harmful pathogens. Or maybe forsake our biology and move on to Silicon ?
Not sure what your point is. If you want to inject genetic material inside an organism to destroy one cell - with the mRNA platform you can only do it once. It won't repackage itself and 'infect' another cell.
If you want to make conditions inhospitable for an organism, you can cause a mass-scale change that affects multiple cells via a drug.