Bob is unquestionably the best runner of his era. He was the first & still the only (American born)3K-10K runner who believed he could compete with the Africans. He was also competitive over a long period of time. It is likely the best Americans of this generation look up to Kennedy as the example they wish to follow.
As to the question of where Bob's career ranks compared to other Americans it is difficult to compare runners of other eras. Shorter has to rank #1. Two Olympic medals speak for themselves. Mills & Schul have Oly Gold & thats hard to argue with. As a runner coming of age in the Prefontaine era I have to make a case for Steve as the best purely US runner competing against other US runners.
I know, I know, many of you are tired of hearing about Prefontaine. However, his dominance against other US runners was thorough. First,look at his number of NCAA CC & Track championships. I did not have Pre's competitive history in making this post, but did Pre ever lose to an American in his Collegiate career over 3M/5K, 6M/10K or CC? Second, at the time of his death he held every American record from 3K to 10K. He also had a 3:54 mile. i can't think of an American who beat him. The guy was a supreme competitior. His 10K AR of 27:43 was a solo effort in terrible conditions without being pushed. Finally, the reason he did not medal in Munich was because he was willing to risk finishing out of the medals to win a gold medal. He had a Bronze locked up, but went for the win instead. If Steve were running today, he'd be a player Internationally, just like he was in the 70's.
I read all posts on this topic & Virgin, Marsh, Liquori, Salazar & others were excellent runners, but none had Prefontaines competitive record against other Americans.
In closing many runners of Pre's era are still waiting for the next Pre. Bob Kennedy came close & that is the finest compliment I can pay him.