It does appear that the pilot was a classic tax protestor:
http://news.yahoo.com/s/ap/us_plane_cra ... protesters
Strangely, perhaps, I have no problem with people flying their planes/helicopters/hovercraft into IRS buildings. I believe it's a sign of a terrible, terrible revolution that needs to, and will, happen. Jefferson himself said there should be a revolution with each new generation, if I have my apocryphal quotes correct. And real revolutions are never "peaceful."
The problem I have with tax protestors is their lame legal arguments. I can't abide losers, and losing is what they always do in court. That is what I despise. If they want to take it to the next level where they might actually have an impact and not be a laughingstock, then more power to 'em, I say. But that's just me and I know there are other opinions here.
Another problem I have with them is the fact that they self-identify with conservatives. Even if Sarah Palin agreed with everything I believed, I'd still consider her a trainwreck. These tax protestors have a lot more in common with Marxism (NOT Marxist-Leninism) than they would ever like to believe.
Marxism states that the middle class must finally realize that it will NEVER join the upper (capitalist) class; and only then will the revolution take place. I believe this is happening now. The rich are getting richer, the poor poorer. And the middle class is slowly coming to grips that this will not change.
HOWEVER, they are mistaking their course of effective action. They believe that the pseudo-libertarian way is their path to salvation, and it will betray them. If only Marx were not so vilified in this country they might understand what needs to, and will, happen next.