Secretary of Transportation Ray LaHood, on his blog, writes: "Why devote resources to a transportation mode that fewer than 10% of the nation is using? Well, bike infrastructure is relatively inexpensive--particularly if you compare it to, say, adding a lane to an existing roadway. Now, imagine if those people who do bike around chose instead to make all of their trips in single-occupancy vehicles. Our already congested roadways would be brought to a halt.
So, even for those folks who have no interest in bicycling, this relatively low investment actually pays dividends for those who still choose to drive. Everybody wins."
You can also hear Secretary LaHood talk about bicycle infrastructure in this recent NPR interview: