The UK PM would have expected his public to understand more from his poppy-wearing than a general sympathy with “peace”:
From Wikipedia re “Poppy”:
“…The poppy of wartime remembrance is Papaver rhoeas, the red flowered Corn poppy. This poppy is a common weed in Europe and is found in many locations, including Flanders Fields. Canadian surgeon and soldier, John McCrae wrote the poem In Flanders Fields on May 3, 1915, after witnessing the death of his friend, Lt. Alexis Helmer. The opening line of the poem vividly describes the image of the poppies blowing in the wind amongst the many crosses that mark the resting places of fallen soldiers.

In 1915 US professor Moina Michael inspired by the poem published a poem of her own in response, called We Shall Keep the Faith. In tribute to the opening lines of McCrae’s poem — “In Flanders fields the poppies blow / Between the crosses row on row,” — Michael vowed to always wear a red poppy as a symbol of remembrance for those who served in the war.[3] Thus the plant became a symbol for the dead World War I soldiers.

In many Commonwealth countries, artificial, paper or plastic versions of this poppy are worn to commemorate the sacrifice of veterans and civilians in World War I and other wars, during the weeks preceding Remembrance Day on November 11.

In the United States, it is common practice to wear “Buddy Poppies” (artificial, paper or plastic versions sold by the Veterans of Foreign War) during the weeks preceding Memorial Day, the last Monday in May to commemorate the sacrifice of veterans in the various wars;[4] whereas Veterans Day on November 11 is used to honor “living” veterans. It has been adopted as a symbol by The Royal British Legion in their Poppy Appeal.

In Canada, poppies are distributed by the Royal Canadian Legion and the Anavets organization each fall prior to Remembrance Day. SNIP:

In New Zealand and Australia, plastic poppies are widely distributed by the Returned Services Association leading up to ANZAC day (April 25).

The California poppy, Eschscholzia californica, is the state flower of California.”

The Opium Trade, Opium Wars etc: the major players in the British Empire’s sponsorship of the opium trade were the Jardine-Matheson company based in Scotland, and the Sassoon family of Bombay. The East India Company’s involvement was minor compared to these two enterprises.
The Sassoon dynasty presents a particularly fascinating saga, beginning with the end of their career as Moorish potentates in Spain with the accession of their catholic majesties Fernando y Isabela. They resumed as functionaries of the Caliphate first in Morocco, then moved their base to Baghdad for the next few centuries. Political changes in Baghdad forced them to flee to Bombay, where they hung on in reduced circumstances until the coming of the British Raj and the opportunity to enter the Export business.

The fabulous profits gleaned from the opium business made them one of the world’s very richest families, allowing them to move their base of operations from the Far East to London, have the family ennobled by Queen Victoria, (cf Baronet Sassoon; Sir Victor Sassoon et al), intermarry with the Rothschild family, and distinguish themselves in various other ways you can learn all about by clicking Google:)
One additional fact which may be of interest: several online sources report that upon the establishment of the State of Israel, the Mumbai branch of the family “made Aliyeh” en masse, lock stock and financial holdings.
Sir Victor died without issue, and since his day the Sassoons have been much less conspicuous. But no discussion of Opium can ignore the roles of the Sassoon or of the Jardine-Matheson interests, which is quite an interesting tale itself.
Thanks again to Dr Saleem for his excellent work:)