Some have suspected that he was a concealed Jacobite, and that he had affected to acquiesce in the Revolution only in order that he might be better able to assist in bringing about a Restoration: but it is probable that his conduct is rather to be attributed to faintheartedness and poverty of spirit than to zeal for any public cause.

He seems to have thought resistance hopeless; and in truth, to a military eye, the defences of Londonderry appeared contemptible.
The fortifications consisted of a simple wall overgrown with grass and weeds: there was no ditch even before the gates: the drawbridges had long been neglected: the chains were rusty and could scarcely be used: the parapets and towers were built after a fashion which might well move disciples of Vauban to laughter; and these feeble defences were on almost every side commanded by heights.

Indeed those who laid out the city had never meant that it should be able to stand a regular siege, and had contented themselves with throwing up works sufficient to protect the inhabitants against a tumultuary attack of the Celtic peasantry.

Avaux assured Louvois that a single French battalion would easily storm such defences.

Even if the place should, notwithstanding all disadvantages, be able to repel a large army directed by the science and experience of generals who had served under Conde and Turenne, hunger must soon bring the contest to an end.