Isn't there obvious confounding - the increased suicide in the medicated vets is due to the reason they took the meds in the first place (they were at high risk) - not the meds??? This seems blatantly obvious.

I'm not pro meds, I'm pro science. If a RCT showed that vets at high risk of suicide died at higher rates, that would be convincing. But at the moment, all you've shown is that vets at high risk of suicide die from suicide at higher rates than vets at low risk, and that meds don't completely attenuate the risk.

You're a smart man. Why doesn't this line of argument convince you? Apart from the fact that it doesn't fit your perspective. The fact that you don't rebut it and explain why it's not relevant is concerning.