This is how wars begin: not through the rash actions of erratic warmongers, but through the slow confrontation of irreconcilable differences. When the threat of inaction appears to exceed the threat of action and compromise is off the table, conflict looks unavoidable.
North Korea and the United States appear to be well past the point of compromise. That's not to say that a war between North Korea and the United States is inevitable, though. Changes in intelligence assessments, in leadership, in interpretations and in perceptions can always intervene unexpectedly. Or it may be that our core assumptions are simply wrong....