UNIONS MATTER. That’s the lesson of National Grid’s six-month lockout of 1,250 United Steelworkers.

Withstanding the latest in a series of attacks on workers nationally, the men and women of Locals 12012 and 12003 held firm for 28 weeks against the hardships imposed on them and their families by a multinational, multi-billion dollar corporate behemoth.

British-based National Grid created the crisis not because it is struggling financially or its future is in jeopardy – it made $4.8 billion after taxes last year. The utility did it simply because it believed it could. The company miscalculated badly, however, because the steelworkers did not break, holding the line while gaining strong public sympathy and political support behind them.

Think about it. Imagine the problems created for unpaid federal workers by the mindless shutdown of the United States government, now in its 27th day. Now multiply that by eight, the length of the 200-day National Grid lockout.

This lockout was not an isolated incident but part of an established pattern of legal, political, and ideological assaults on workers and labor unions across the nation. The goal is clear: extract more profits at the expense of those who do the work.

If a corporation is preparing to sell part of the company or boost “shareholder value,” the playbook is pretty simple — slash worker retirement and health care benefits, raise the share price, and then cash in.

In unscrupulous privately owned companies, abuses happen frequently and with little or no public notice or news media coverage. Without the strength of a union, individual employees are at the mercy of owners who all too often force them to work longer days and weeks without paying overtime as required by law or pay below the minimum wage.

This is wage theft and the Massachusetts AFL-CIO is a leading advocate for legislation on Beacon Hill to give Attorney General Maura Healey and workers better tools to crack down on wage theft estimated to cost workers $700 million a year in Massachusetts alone.

 Unions have created a pathway to the middle class for generations of Americans and have led virtually every effort that produced advances in employee benefits and workplace safety.

The labor movement continues to stand for fairness and equity for all workers. Unions provide a bulwark against greed-driven attempts to roll back this progress, serving as the front line of defense against these corporate and political machinations. Over time, these assaults have widened the income-inequality divide, stoked anger and resentment, and pitted American vs. American.

The United Steelworkers’ courageous stand against National Grid is one more example of why unions matter.

Steven A. Tolman is president of the Massachusetts AFL-CIO.