[2] He joined the Thames Miners' Union which by 1901 was seeking increases to wages and safer working conditions, but were perpetually refused by the owners.

As a result of this the union and Armstrong himself grew disillusioned with the arbitration process and became attracted to the more radical idea of syndicalism they were introduced to through the New Zealand Federation of Miners (to whom they were affiliated).

By this time the labour movement were voicing concerns about cost of living increases for workers, servicemen and their dependents and, by the end of the year, were actively protesting government imposed conscription.

In 1917 Armstrong gave a speech at a street-corner meeting stating that the motivation for conscription was mostly due to the government wanting to increase their control over workers, not out of a necessity to defeat the Central Powers.

[4] Whilst a member of the city council he was a perpetual advocate for public works schemes and municipal housing to both create employment and improve the quality of life for workers.

As a unionist who had spent a year in Lyttelton goal for sedition, he had no chance of being elected in this well off electorate, and the incumbent, Leonard Isitt, was successful.

[7] He tirelessly advocated for his working-class constituents in parliament to increase wages, improve housing quality, and for the need of active government policies to reduce unemployment which rose rapidly in the 1920s.

One noted occasion led him to impugn the government who seemed content the country be little more than 'a cowyard' and ministers were 'only capable of thinking in terms of beef and butterfat'.

He also initiated an expansion of the Employment Promotion Fund which developed marginal farmland and improved local infrastructure through subsidised labour.

[2] However he publicly defended conscription by arguing it to be a wartime necessity and that with the stipulations of pricing controls and an avoidance of using the measure against workers, his position was consistent, to an extent, with those in 1916.