What is one example of grim humor in The Tell-Tale Heart?

 the beating of the old man's heart when he is buried under the floorboards.

Explanation:

The main ideas of the speech are:

The Berlin wall represents the suppression of freedom around the world. The wall represents the danger of totalitarian governments. West Germany prospered with the help of the Marshall Plan created by the USA. The Marshall plan was not aimed at fighting East Germany, but at fighting hunger, despair, poverty and chaos. West Germany embraced the Marshall Plan and prospered, East Germany embraced communism and failed. This proves that freedom is the winner. Democracy and capitalism are winning all over the world, while communism is being defeated even in Russia. Russia is being forced to change its policies if it does not want to become obsolete. This means that communism will be defeated worldwide and the Berlin Wall will fall. When that happens, western nations will be ready to help eastern nations.

Explanation:

Ronald Reagan's speech was made to show how it was a matter of time before Communism was defeated and suppressed worldwide. In Germany this would be no different and the proof of this was the imminent fall of the Berlin wall.

Reagan takes advantage of the opportunity to reaffirm the role of the USA in the fight against communism and oppression, as well as the relevance of the USA in the success of Western nations, such as West Germany.