Intel agencies? Talk to anyone who is in the intel field (who are actually in it with appropriate clearances not just some jabroni that has had an intelligence briefing 12 years ago for some reason) and they will tell you that intelligence in the US is abysmal. These fools (meaning every talking head on TV and radio) don't know what they don't know. Testing? Maybe it works, maybe it doesn't (a full 1/3 have false negatives?!?). Treatments? Maybe..hell, we don't really know. We will know so much more about this about a year after it's over with. And we will see that what we did to "combat it" will have been wrong, too. Best thing I can do for me and my family is to just assume that EVERY SINGLE PERSON I SEE has the virus. EVERYONE. Once you go along with that and plan accordingly, the chances of catching it probably go down by a significant amount.
I believe there are now reports that were presented months ago saying that this could become a real issue, though.
And to your final point, even CNN's Dr. Sanja Gupta was saying on March 18 to act as if you might be carrying the virus and distance yourself as you would if you knew you were sick. Yet here we are, with many places lacking a shelter in place order, only recent moves to curb beachgoers and the governor of Georgia only 'recently learning' that people could be sick without showing symptoms.