You can become an "arms merchant" for the cloud. You can build your own clouds and rent them as "public clouds." You can seek to build clouds for large clients and create "private clouds," then "hybrid clouds" in which workloads move between the public and private cloud realms. HP and Dell are trying to do all these things. HP has some great assets in storage, both offer servers, HP has networking through the former 3Com, and both are offering to bring suites of cloud software, services and their own networks of public clouds to the market. But this is a new business to both. As Dave Chernikoff writes at ZDNet, it's a very competitive business. Margins are going to be squeezed and brand advantage will be minimal. We already know from HP's write-offs this week that the old "enterprise services" and outsourcing businesses were a dead end. We know the PC business is fading, that there is nothing HP or Dell can do to replace it and that cloud is going to be a tough market to crack. Does it remind me of what happened to Digital Equipment, to Wang, and to SGI? Yes, I'm afraid it does. But it's technology evolution in action. Nothing stays the same. Everything, and anyone, can be replaced, sometimes suddenly and without notice. At the time of publication, the author had positions in F, IBM, GOOG, MSFT and AAPL. This article is commentary by an independent contributor, separate from TheStreet's regular news coverage.