Piers Morgan writes (and I’ve seen other comments that suggest the same):
[D]uring a public rally on the Washington Monument grounds [in 1966, t]he crowd present broke up into small discussion groups and petitioner joined a gathering scheduled to discuss police brutality. Most of those in the group were quite young, either in their teens or early twenties. Petitioner, who himself was 18 years old, entered into the discussion after one member of the group suggested that the young people present should get more education before expressing their views.[P]etitioner responded: “They always holler at us to get an education. And now I have already received my draft classification as 1-A and I have got to report for my physical this Monday coming. I am not going. If they ever make me carry a rifle the first man I want to get in my sights is L.B.J.” “They are not going to make me kill my black brothers.” On the basis of this statement, the jury found that petitioner had committed a felony by knowingly and willfully threatening the President.
The Supreme Court reversed the conviction:
We do not believe that the kind of political hyperbole indulged in by petitioner fits within [the term “threat"]…. The language of the political arena … is often vituperative, abusive, and inexact. [Watts’] only offense here was “a kind of very crude offensive method of stating a political opposition to the President.” Taken in context, and regarding the expressly conditional nature of the statement and the reaction of the listeners, we do not see how it could be interpreted otherwise….
And “[t]aken in context,” it’s clear that Madonna isn’t threatening to bomb the White House:
Yes, I’m angry. Yes, I am outraged. Yes, I have thought an awful lot about blowing up the White House. But I know that this won’t change anything. We cannot fall into despair. As the poet W.H. Auden once wrote, on the eve of World War II, we must love one another or die. I choose love. Are you with me? Say this with me, we choose love….
Of course, sometimes the focus on meaning in context — rather than the literal words — can make something into a true threat even if there is no express reference to violence. “Nice restaurant here; would be a shame if anything happened to it, you really ought to buy some insurance” could be a true threat in the right context.
Likewise, that Madonna just literally said that she thought about bombing the White House, rather than she would bomb the White House, wouldn’t by itself preclude a finding of a true threat. “I’ve thought an awful lot about killing you” might well be a death threat, even without any express statement such as “I will kill you,” again depending on the context.
But in any event, in this context, Madonna’s statement isn’t a threat of violence — not in the eyes of the law, and not, I think, in normal everyday understanding.
[Totally irrelevant to the free speech issue, but an interesting tidbit: In a later edition of the poem, Auden changed the line to “we must love one another and die." Query how things would have come across if that were the line Madonna quoted ….]