Haig had to agree but declined to loan three cavalry divisions as well. Dissatisfied by Plumer's plan for a limited offensive to retake Messines, Haig urged him to retake the high ground around Ypres (the British objectives from the previous autumn) and be prepared to land a division on the coast at Ostend. Plumer was sceptical as late as 13 September. On 10 September Haig, on a brief visit to London, told Lord Milner (Secretary of State for War) that 77,000 prisoners and nearly 800 guns had been taken in four weeks, and that German morale was disintegrating and it was "the beginning of the end". He thought that the aim should be to win the war that year, and by spring 1919 at the latest, not July 1919 as the politicians had in mind, and urged that all available able-bodied men and transportation in the UK be sent, as well as men earmarked for the Royal Navy and for munitions production, even at the cost of reducing future munitions output. On 12 September, the day the Americans attacked at St Mihiel, Third Army began moving up to the Hindenburg Line by attacking at Havrincourt, beginning a fortnight of grinding progress against Germans who were still fighting hard on that sector. On 18 September Fourth Army attacked at Epehy, reaching the Hindenburg Line. Haig received a congratulatory note from Wilson saying "you must be a famous general", to which he replied that he was not (as this would have meant currying favour with Repington and the Northcliffe Press) but "we have a number of very capable generals". By this stage the British cavalry were weakened just as they were playing a much large role in the war. 2nd Cavalry Division had been broken up to provide a squadron of cavalry for each division, leaving Kavanagh's Cavalry Corps with only two cavalry divisions, supported by a brigade of infantry in buses. (By contrast, of Allenby's 11 divisions in Palestine, 4 were cavalry.) Haig spent the whole of 17 September at a cavalry pursuit training exercise, followed by a conference, and then wrote up the report personally. He still hoped that cavalry could conduct a deeper exploitation towards Ghent or Valenciennes, but no longer had the resources to do so. With few functioning tanks and armoured cars left, the British were hampered by lack of cavalry. Milner and Haig met again at GHQ in France (21 September) – Milner warned Haig that manpower would not be available for 1919 if squandered now and told Wilson (23 September) that Haig was being "ridiculously optimistic", might "embark on another Paschendal (sic)" and that he "had grave doubts whether he had got inside of DH's head"; Wilson thought the War Cabinet would have to "watch this tendency & stupidity of DH".