1.What do you think of players willing to spy on an alliance?
2.What do you think of Alliances & alliance leaders that attempt to plant player spies?
Please share advice for others on ways to prevent their alliance being infiltrated (SW)
I'm not on this world so don't care about the politics. in answer to your questions:
1. There are several brackets of spies.
Type 1
the lowest bracket is those running in fear from an attacker, may offer to spy against their alliance in return for a personal NAP. In this instance the player spying has admitted defeat, and is probably simming the game, and is much more of a solo player. Their loyalty is weak no matter who's alliance they are in. Very susceptible to disinformation.
Type 2
These spies know what they are doing, they have personal goals but show no loyalty to anyone apart from their own agenda. They are often much better players, but again susceptible to the ancient art of disinformation. They are also much more likely to out themselves looking for information, or acting erratically. They are driven by a desire for the type of political control you don't even get as a major alliance leader. They are often clever and strategic, but can become too clever.
Type 3
The Jack. Unlike type 2, they have motives and promises of power, they are better players than type 2 and generally have some decent leadership skills. They specialise in overthrowing leaderships, stealing members and getting into your council chambers. They are often extremely difficult to uncover, since their disguise is generally well planned by the sender. Type 3 spies that know their game rarely fail, and rely on a lack of reputation to be able to repeat the instance over and over again. These are people that pride themselves in their learning skills and adaptability, and often gain alot from the planning of the officer they work under. It is as much an RL learning experience as it is a game, and the skills will stand you in good stead for your next job interview.
Type 4
The external spy, normally a diplomat or negotiator outside an alliance that plants information into another alliance leadership for their own cause. Type 4 spies are right at the top end of the ability scale, they can generally outwitt 90% of the populace and have strongly persuasive abilities. You will never know they got the information out of your mouth, but they will convince you that they got it from someone else in your alliance. They will set you looking for a spy that is not there, and hence completely break down the trust relationship within your alliance, between your members and leadership, especially friends of those falsely accused.
2.The better question would be, what would you think of leaders who recruited your spies. I will tackle the following instances:
MRA's
every MRA in the game is littered with people's spies, most people are quiet happy to state that MRA's deserve to have spies to teach them a lesson in recruitment. So why plant a spy in an MRA? It is likely that most spies placed in MRA's are type 3 spies, designed to steal their good players so you can demolish the noobs quickly. It is an accepted practice throughout the game even by anti-spy players.
Practitioners of Propaganda Recruitment
Ever mailed an enemy alliance, with a join us or die message? Well I think that you should think again, often the most lethal spies are inserted by this method. Someone who was originally a type 2 spy may start showing the aspects of a type 3 due to the fact that he has a focus point of hate. Again I can share no sympathy for alliances that recieve spys through propaganda.
Merge Fail
Some merges fail, and players split between alliances. This generally gives you type 1 spies, players that were in the same alliance before still communicate. Their leaders receive the information, but the player that provided it, provided it unintentionally. This brings in the Player vs alliance loyalty argument, but most players will find they are more loyal to specific ingame friends than the alliances they are in, no matter of their feeling on the topic. You just have to get over that when a merge fails, then you may lose information to other alliances.
Allied Friends
This goes back to the above topic of player vs alliance priority. Leaders may keep tabs on an ally that is proving a little untrustworthy by using such arrangements between players. These will be originally type 1 spies (though again they will not be aware of it). However in the event of a betrayal they have the potential to become type 2 or type 3 spies, looking for revenge from a backstabbing incident.
So in order to answer about leaders and spies that plant them... the alliances they end up in are generally at fault for their presence. It is not, and never will be cheating, the ancient art of accurate disinformation nullifies most common spies, and it is up to leaders to implement the measures to deal with spies they recruited. "Survival of the Fittest" terms not just war, it also relates to the quote "You cannot attack what you cannot see", people that are fit enough to be invisible from the public eye have it on both sides, and at the end of the day will be the only survivers of the carnage of a war.