Event Police

In Poul Anderson's Time Patrol series, people from our future can travel into their past, therefore the Time Patrol protects known past events. In James Blish's "Beep"/The Quincunx Of Time, an organization called the Service receives messages from its future, therefore that organization protects known future events. One Service agents says:

"'...the Service is in no sense a thought police. We're interested only in acts. We're an Event Police.'"
-James Blish, The Quincunx Of Time (New York, 1983), p. 106.

The Time Patrol is another Event Police.

In the world-wide Bureaucratic State of Blish's Cities In Flight:

"The omnipresent thought police were instructed in the formulae of ballistics and other disciplines of astronautics, and could detect such work - Unearthly Activities, it was called - long before it might have reached the proving-stand stage."
-James Blish, Cities In Flight (London, 1981), p. 238.

Thus:

George Orwell's dystopia, 1984, introduced the Thought Police who denied the reality of the stellar universe;
Blish's "omnipresent thought police" suppressed space travel;
Blish's "Event Police" opened up intergalactic expansion;
Anderson's Time Patrol is comparable to Blish's "Event Police."

Blish found two creative uses for Orwell's phrase, "Thought Police." We are surprised when we realize that "the Service" is not an abbreviation for any such phrase as "Secret Service."

The Service monopolizes not only reception but also transmission of messages from the future and therfore enforces this rule:

"'The date of death of a sentient entity must never be mentioned in a Dirac 'cast.'" (p. 110)

A Service agent reflects that:

"An Event Police might have its justifications; but an Assassins' Guild, none." (ibid.)

But is the Time Patrol an Assassins's Guild?

Manse Everard is prepared to contemplate the assassination of a man who has become a personal causal nexus;

in any case, the Patrol protects a history that is full of murders, assassinations, executions, wars, massacres and pogroms.

By contrast, the future protected by the Service is increasingly utopian I think because of a circular causality paradox:

the Service will receive a message describing a massacre only if such a message is transmitted;
such a message will be transmitted only if a massacre occurs;
a massacre will occur only if the Service has caused it;
the Service will cause a massacre only if (i) the organization has received a message describing the massacre and (ii) Service members are morally capable of causing a massacre;
however, Service members are not morally capable of this;
therefore, no such message is ever received.

If the Merseians or the Draka monopolized the Dirac transmitter, then they would use it to conquer the galaxy.