Why did the journal jump to the conclusion that the spanish were responsible for the explosion of the maine?

The Spanish investigation team claimed that the explosion was only an accident caused by some internal problem on the ship; American investigation said the explosion must have been caused by a Spanish mine in the harbor. Spanish authorities felt that the US was trying to intimidate them by interfering with Spanish sovereignty trying to affect Spanish policy toward Cuba

Because the Maine was supposedly carrying supplies to the Cubans.

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