Similar to this question, I'd like to be able to fire off a query (from an external application) to determine when someone is removed from a Salesforce Campaign. The question I linked has a good solution for determining when a campaign is modified (provided by a user) like so:
SELECT Id FROM Campaign WHERE Id IN (SELECT CampaignId FROM CampaignMember WHERE CreatedDate = TODAY)
Using similar logic (and assuming I can't just view these things in Salesforce itself), how can I determine if someone is removed from a campaign? There doesn't seem to be a
CampaignMember field available for that.