Saving "Secular Washington"

On a recent business trip, I ran across this church flyer in a hotel in Washington, D.C. The vision statement has bothered me every since. Their vision is to "...make an impact on secular Washington..."

How do they define secular Washington?

• People not at McLean Bible Church?
• People not in church?
• People who drink, smoke, chew, or go with girls who do?

What about Muslims, Buddhists, Catholics, or Methodists -- Secular?

I'm confident the good people at McLean Bible Church have intentions to make a positive difference in their community, but the separation of what is "secular" and what is "non-secular" (spiritual, holy, Godly, churchy, non-loud, non-pierced?) confuses me. Why make the distinction?