[QuotedForTruth]

Its more about the somewhat likely probability that a single launch provider will have a failure that necessitates a lengthy investigation during which they are grounded. Its nice in that situation to have another launch provider who can pick up essential missions.

[ceejayoz]

That's certainly a risk, but "we're the only launch provider in the US, and we just raised prices from $250M to $2.5B, and any potential competition will take 5-10 years to get up to capability" is a big risk too. The DOD isn't gonna launch GPS satellites on a Progress.