There are mounting indications that a quarter-century during which the class struggle in the US, Britain and other industrialized countries was artificially suppressed is coming to an end. Recent weeks have seen a wave of strikes and protests in France against a reactionary labor “reform” law, carried out in defiance of a state of emergency imposed by the right-wing Socialist Party government; a general strike by Greek workers against austerity measures implemented by the pseudo-left Syriza party; strikes by junior doctors in Britain against social cuts carried out by the Conservative Party government with the support of the Labour Party; a strike by air traffic controllers in Belgium; and strikes by workers in India and China.

In the US, a strike by 39,000 workers against the global telecommunications giant Verizon, the biggest American labor stoppage in many years, is now in its sixth week. This is a significant, although still initial, expression of a growth of the class struggle in the center of world capitalism. It coincides with a series of strikes and sickouts by teachers in Detroit and other cities, and a wave of social protests such as the demonstrations against the poisoning of the water supply in Flint, Michigan and protests against police killings of unarmed workers and youth.

All of these struggles take place in the face of the treachery and sabotage of the trade unions. The unions at Verizon, the Communications Workers of America (CWA) and the International Brotherhood of Electrical Workers (IBEW) have isolated the Verizon workers and done nothing to oppose company strikebreaking and violent attacks on picketers by scabs, who are being escorted and protected by the police.

They are desperate to end the strike and impose a sellout contract. In a sign of the accelerated drive to end the walkout, 88 Democratic congressmen, allies of the CWA and the IBEW, issued an open letter Thursday calling for an end to the strike.

In 2015, the United Auto Workers union barely succeeded in suppressing a rebellion of autoworkers against sellout contracts they signed with the Detroit-based auto makers. Despite the best efforts of the union bureaucracy, however, the past year has seen a modest but significant increase in strike activity.

Figures released last February by the US Bureau of Labor Statistics (BLS) quantify the inflection point in the class struggle in America. They show a 400 percent increase in the number of days lost to major labor disputes in 2015 as compared to the previous year. The bulk of the increase is accounted for by the four-month strike of 5,000 oil workers across the US that year and the lockout of 2,200 steelworkers by Pittsburgh-based Allegheny Technologies.

The Verizon strike will dramatically raise the figure for days lost to labor stoppages for 2016. Labor contracts, meanwhile, are still pending for 573,000 postal workers, hundreds of thousands of state and local public employees and teachers, and hundreds of thousands of retail workers.

The level of strike activity remains far below what was commonplace from the 1940s to the 1980s. In 2015, there were 12 major work stoppages (1,000 or more workers) involving 47,000 workers, an increase over the previous year. This compares to the peak year for US work stoppages, 1952, when 2.7 million workers participated in 470 major industrial disputes.

In the 1980s, the AFL-CIO betrayed a wave of bitter strikes against mass layoffs, wage cuts and union-busting, beginning with its sabotage of the PATCO air traffic controllers strike in 1981 and its tacit support for the firing and blacklisting of 11,000 strikers by the Reagan government. This led to decades during which strikes in the US fell to historic lows. The growth of social inequality and record rise in the fortunes of the corporate and financial elite were directly connected to the virtual disappearance of any form of organized class struggle.

The collapse of the financial system in 2008 and the ensuing onslaught on jobs, wages and social programs left the working class stunned and disoriented. But as it became clear that the ruling classes of the world were intent on exploiting the crisis to wipe out all of the past social gains and reduce the working class to penury, workers began to realize there was no alternative to bitter struggle.

The revival of the class struggle is finding political expression in a turn by workers against all of the parties of the official “left” that are backed by the trade unions: the Labour Party establishment in Britain, the Socialist Party in France, the Social Democratic Party in Germany.

In the US, the growth of working class militancy is accompanied by the beginning stages of a profound political radicalization, reflected initially in the broad support for Bernie Sanders, whose claim to be a socialist has magnified his appeal to millions of workers and youth who are rejecting capitalism and looking for a radical alternative. His campaign is a preemptive response to the growth of the class struggle and the danger of the emergence of an independent political and revolutionary movement of the working class. Its aim is to keep this movement trapped within the Democratic Party.

The Donald Trump campaign is likewise a preemptive response to the growth of working class opposition to the existing economic and political setup. Its aim is to direct this movement along chauvinist and nationalist lines and prepare the conditions for the ever more direct use of violence to repress social tensions at home.

The revival of class struggle may be in its initial stages, but it will expand explosively. It is being driven objectively by the crisis of the world capitalist system, which offers nothing but poverty, dictatorship and the horror of global nuclear war. All of the struggles, whether strikes or social protests, raise revolutionary issues and pose the question of political power.

The first task that confronts workers is the need to break free of the reactionary pro-capitalist labor bureaucracies. But as Leon Trotsky explained in the founding program of the Fourth International, the Transitional Program, there are powerful objective forces that facilitate this task:

The orientation of the masses is determined first by the objective conditions of decaying capitalism and second by the treacherous politics of the old workers' organizations. Of these factors, the first is of course the decisive one: the laws of history are stronger than the bureaucratic apparatus.

The urgent and critical need is the building of a revolutionary Marxist leadership to unite all of the different struggles into a single class struggle and provide it with a revolutionary political perspective.