Rockwell exited the defense business in the mid-1990's. Previously they had acquired Allen-Bradley industrial controls in 1985. Today, the A-B base business has grown be essentially the core of Rockwell's business, and has evolved into the largest automation-focused provider in the world. Siemens and Emerson are larger by market cap but have other diverse offerings. Rockwell is $6B in pure play automation sales. This business is globally diversified with almost-guaranteed repeat business related to MRO, in addition to high technology for optimization of "old" assets. Think Heinz ketchup: Warren Buffet buys it and invests in manufacturing improvements... this is done by Rockwell.
It's a great company with a great future. That being said, the last 6 months run-up is extreme and I sold my entire position yesterday. As soon as it corrects 10% I'm going to buy it all back again and more.