Air is a bad conductor of electricity so whatever is closest that will get the lightening to the ground first, it strikes. Therefore, the lightening would sense the tall pole first, and use it as it's conductor.
In the 20,000 leagues under the sea, they had made the important decision on escaping the Nautilus which leads to the climax and main part of the story. Which is the building action leading to major changes around them causing drastic decisions needing to be made, which then leads to falling action, causing them having to rethink decisions and create different resolutions.
