Derf, PHO seems like a great choice, along with FIW, although they both have fairly high expense ratios (0.60%, 0.53%). I had some in the past, but currently only have some individual stocks in the water related sector (BMI, ROP, TTEK, WTS), and DHR has some water exposure. I might add some PHO and FIW though. They've both beaten the S+P 500 over the long run.
With RTX, it's been more volatile than I like to see, compared to LMT and NOC. But for the Aero / Defense sector I went with the broad ETF (PPA), supplemented by some loosely related stocks (BAH, CACI, TDG) that have great long term charts.
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