David Brooks makes an interesting comparison of Obama to Kennedy and to Eisenhower. Brooks notes their two most important speeches: Kennedy's inaugural and Ike's farewell. Of the two, I think that Ike's speech may prove--or already has proved--the more enduring of the two. Check it out here.
Is Obama cautious? Vacillating? Wise? Fearful? It's very hard to say from these seats. However, I agree that normally we want to err on the side of caution.