I disagree that my (extremely broad) diagnosis of the problems with forecasting in America is based on flawed premises. You've provided thorough, correct, and important details here but my comment was aimed at the broader HN audience, not on writing the central argument for a discussion on the historical timeline. I think what I said, "Horrible oversight by the federal govt (read, congress) of our technical/scientific forecasting resources means that our forecasting ability is extremely fragmented and poorly organized." is a very concise summary of the things you've laid out here.
As for the details in your comments, the only thing I disagree with strongly is the comment about investment in computing. While sufficient computing resources are central to good forecasting, the lack of investment by NOAA in computing (I sit at NOAA) is a red herring. ECMWF is significantly better than either of the two available American forecasts because they are just better at what they do, all around. In particular with respect to data assimilation. I've sat at meetings with ECMWF forecasters who have asked for access to my in-situ data products and their pipeline is as simple as "point us to the data please". Their data assimilation pipeline is so much more sophisticated and thorough that catching up on that alone would be a huge huge leap. Mind you, not just '4DVAR' the methodology, but literally the way that the community finds and integrates observational data.
ECMWF, the organization, is quite literally structured to strictly accomplish the goal of 'improve the forecast'. Whereas, again broadly, the American institutions are much more a congolemerate of associated researchers doing individual science projects while small teams work on specific segments of the forecast. Yes, we are attempting to fix this. No, we haven't fixed it yet.
This is not to say I don't think we should fund computing or that computing won't help. But we are quite literally 5-10 years of research behind on multiple fronts.