Politics is no longer an instrument of the democratic process because Democracy has been hijacked by liars and self-seeking opportunists.
There was a time when the British people could rely on elected representatives, at the very least, to keep the best interests of the United Kingdom at the heart of their actions regardless of their individual political allegiances. However, the evidence of the last 40 years or so demonstrates the exact opposite where the systematic demolition of public services, entire manufacturing industries, and whole communities has been on such a scale they are more than likely beyond repair.
And the politicians get away with it, shrugging off all responsibility, shielded by the very thing designed to protect us, the masses, from their excesses. Democracy.