Why a dispute between Austria-Hungary and Serbia escalated into World War I?

July 28, 1914

One month after Archduke Franz Ferdinand of Austria and his wife were killed by a Serbian nationalist in Sarajevo, Austria-Hungary declares war on Serbia, effectively beginning the First World War.

so, based on the research i've done. the u.s. government were always on a wild goose chase just to take down castro. he then retired his trone to his brother raul in 2008 due to some health issues. so it's obvious your answer would be:

castro had no allies from which he could receive aid.

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                                                    -wolfiewolffromsketch