Treason is a famously slippery word, not least for the reason enshrined in the oft-quoted but, because it contains a savage truth, eternally potent rhyme:

Treason never prospers,
What’s the reason?
For if it does
None dare call it treason.

Of what does treason consist in the formally democratic nation state? Generally it must be the conscious decision to act in a way which will weaken the integrity of the nation state.
Betrayal in the old manner of spying or acting for an enemy in war is still part of that, although the primary treason in the modern formally democratic state is more insidious.

It is the abrogation of the sovereignty of the nation state by immersement in larger political entities and through the signing of treaties which restrict the opportunity for national self-determination.

The first is that the treasonable activity may be misrepresented by the party or politician. A classic example of this is Britain’s entry into what is now the European Union (EU). The British electorate were undeniably deliberately misled by the 1970 Tory manifesto into believing that they were merely joining a free trade area. They were deliberately misled again during the 1975 referendum on Britain’s continued membership. They have been deliberately misled consistently in the 25 years since the referendum, being told by every government that British sovereignty is not being lost, when massive amounts have been ceded. That is treason by any meaningful definition that has ever been used in the past.

In the case of Britain, the most dramatic formal act of damaging the nation state has been our membership of the EU, that is only one of a number of serious attacks on the British state and people. The permitting of mass immigration is a profound form of treason, for mass immigration is a form of conquest.
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