With the Billions spent on intelligence how could the intelligence community miss Donald Trump?

The NSA records foreign phone calls, American intelligence spy's on Russia and Putin a former KGB officer running a super power with missiles pointed at the United States. Donald Trump a well known con man billionaire, who does not pay taxes with questionable income and clear ties to Russia runs for President and has the audacity to publicly ask Russia to spy on his American opponent a former Secretary of State. Trump also hires known Russian proxies.

Just how is it possible he has not been investigated by the most sophisticated best funded intelligence law enforcement agencies known to exist? This has to be in all human history the most public obvious betrayal ever recorded.