Play into

North Korea takes pride in standing up to its much larger archenemy. That is why the Korean War armistice of 1953 — a truce that was seen in Washington as a failure to bring the conflict to a close and to stop the march of communism in Asia — is celebrated in Pyongyang as Victory Day. To fight the United States to a draw is tantamount to victory, as far as the North Koreans are concerned.

If President Trump thinks that his threats last week of “fire and fury” and weapons “locked and loaded” have North Koreans quaking in their boots, he should think again. If anything, the Mao-suit-clad cadres in Pyongyang are probably gleeful that the president of the United States has played straight into their propaganda. They know that their country is a tiny hedgehog, but it seems to have disturbed the tiger.

What does 'play straight into their propaganda" mean?