Question

The President detoured to Chicago for a special meeting.
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What does the sentence above mean, #1 or #2? Is the special meeting in Chicago or anywhere else?

1. The President visited Chicago on the way to the White House to have a special meeting there (in Chicageo).

2. The President had to go to a place to have a special meeting, but becuse of traffic jam he had to go around to Chicago. He had to pass through Chicago to go to the place where meeting will be held.

Answer 1

It does not say he was on his way to the White House; he could have been going anywhere. It says Chicago was a variation on the route he had planned, whatever that was. There was a "special" (unscheduled?) meeting in that city that he wanted to attend.

It means neither #1 or #2.