ECONOMY AND THE UK MINERS' STRIKE 31 the NUM which had first humiliated and then defeated the previous Tory government under Edward Heath. But revenge, costing the government over £ 2 billion (the effect of the strike on tax revenue and nationalised industry profits), can hardly be the full story. The NUM plays a pivotal role in the trade union movement, and its defeat would be a major defeat for all trade unions. This would be important politically, but economically, as well, as workers' ability to resist shop-floor rationalisation and further evasion of trade union rights would be seriously "weakened. As Chancellor of the Exchequer Lawson was incautious enough to admit, success in this respect would make the costs incurred by this strike a "good investment" from the point of view of government.