100 years ago this week Winston Churchill and the British war command agreed to "prepare for naval expedition in February  to bombard and take the Gallipoli peninsula, with Constantinople as its objective."
According to Taner Akcam and Donald Bloxham, the British decision on the Straights, as well as the earlier Turkish failure at Sarikamish against the Russians, served as important triggers that accelerated the Young Turks' plan for the Armenians. Churchill also mentions that in his 1929 memoirs.
A detailed review of Churchill's role in the preparation of the attack on Constantinople is available here, including this curious passage:
"In the Eastern Mediterranean, off the Turkish port of Alexandretta (now Iskenderun), on 20 December , under threat of bombardment from the six-inch guns of a British light cruiser, Doris, the local Turkish authorities agreed to blow up their two railway engines and several military stores. Having no explosives, they asked the British naval captain to send some of his own sailors and explosive charges. The Turks then supervised the actual destruction, under the beam of the cruiser's searchlights. Later that evening, Doris sailed away." (A similar incident occurred in the 2008 Russia- Georgia war, when authorities in the port of Poti allowed Russian military to come into the port and blow up much of the Georgian naval force there.)
For more on the connection between the British/ANZAC attack and the Armenian genocide see Robert Manne's article.