KnC - I am not sure I would put much faith in the defence opinions of Simon Jenkins who called for a 100% defence cut in 2010, in 2016 he condemned Corbyn's implied promise not to support NATO commitments, while questioning NATO's current purpose and being against it 'giving defensive assurances to non-Nato states along Russia’s borders'. HIs view of risk seems to be heavily biased towards probability and against consequence.
Asturias, I don't deny defence isn't voters highest priorities but our politicians aren't mandated delegates but representatives who should judge for themselves what is in the country's best interests. Given the nature of the poll you quote if 100% of those polled had defence as their fourth highest priority it would have scored 0%. I am pleasantly suprised that 9% had it in their top three. For centuries UK governments have slashed defence expenditure at the earliest opportunity and not been in position to face a serious threat. It may be that the threat of the nuclear weapons Jenkins so despises coupled with the NATO mutual defence may reduce threat of attack on British territory to a minscule level but credible conventional forces are needed to deter piecemeal attacks on British interests.
I am not a big fan of Wallace but he is almost certainly better than the probable alternatives Boris could have chosen. Like all Defence Secretaries his effectiveness is governed by the Treasury's final word. An army brat who probably saw service as his duty, deployed under Op Banner when death or serious injury was a real possibility and took a positive decision about his future instead of staying to the end of his commission lacking motivation. Historically, the Army and the Navy (not certain about the Airforce) required a supply of officers on short service commissions to meet their operational needs.