 That meant that he alerted the Secret Service to the threat. But still, nobody detained the man and nobody pulled Trump off the stage, even though there's only one reason a suspicious person would be using a rangefinder right outside of a Trump rally. And everybody knows what it is. There is no conceivable innocent reason for a guy to be lurking around the site of a campaign rally with a rangefinder. Or if there is an innocent reason, the innocent reason is significantly less plausible than the sinister reason.