The ex-Highland MP has raised concerns over the absence of a Scottish MP in the Treasury for the first time in a generation.
The SNP swept to a landslide victory north of the Border in the May election, returning MPs in all but two of the country’s 58 constituencies.
But Mr Alexander said yesterday: “In the end what you have is Scottish Nationalists in Scotland totally impotent in terms of what happens in the UK.
“Frankly this is the first time since devolution that there hasn’t been a Scot in the Treasury – in a Cabinet position.
“I think Scotland in a way has less say over what happens in this country without one minister in the Treasury even though it’s got 56 SNP MPs.”
Mr Alexander, who lost his seat in the election, was one of the key figures in the coalition government and was George Osborne’s No2 as chief secretary to the Treasury.
He said the Liberal Democrat election meltdown in key constituencies was down to the success of the Conservatives in raising fears over the prospect of the SNP holding the balance of power.
“I still felt that actually our support being concentrated in a lot of our constituencies that we could hold enough seats in the election to come through and potentially play another role in government,” he added.
“I think the reason that we didn’t do that was because the Conservatives very effectively played this tactical squeeze message that said that if they didn’t have a Conservative majority that people who just six months before tried to break the United Kingdom would then be allowed through the back door to govern it.
“Voters in England to an extent that I didn’t recognise during the campaign really resented the idea.”
Mr Alexander, who lost the Inverness, Nairn, Badenoch and Strathspey constituency to Drew Hendry of the SNP said he is still considering what he will do in future.
But he has not ruled out a return to politics and insisted that his career had only been “interrupted”.
He admitted that the election had been “disastrous” for the Liberal Democrats after the party was left with just eight seats.
But he defended Nick Clegg’s role as leader and rejected claims anyone else could have done better.
“I don’t really see the point of picking over things that we might have done over the past three or four years,” he said.
And he is not taking sides in the current leadership battle between MPs Norman Lamb and Tim Farron.
“I’ve said to both teams that I hope they will maintain the credible stance on the economy that we built up,” he said.
“When you look at our five years in government we achieved a great deal for the country, we really helped to turn the economy around.”