Douglas Bell asks me a very fair question over at his blog in response to my last post: "Would Senator Smith have spent the time grinding with Brian Topp if he thought that 'there is no reason to think that the NDP -- with Jack Layton or Thomas Mulcair as leader -- will be any different than it has been for the last 45 years'?"
While I won't even start to comment or speculate on Senator Smith's role in negotiating the coalition or his views of the NDP (though the image of Senator Smith "grinding" with Brian Topp does evoke images from Dirty Dancing for me, and not in the good way), I will give my opinion. While the Liberal party may have a different leader, the options facing the party in response to the budget are exactly the same as they were the day before the fiscal update was presented:
1. Vote it down and cause an election;
2. Vote it down and enter into a coalition (though obviously the Liberals could have chosen a different leader to head up the coalition);
3. Oppose it but abstain/have a bunch of MPs sick/etc such that the budget passes; or
4. Support it outright.
As far as I know, every single Liberal MP left the fiscal update saying at the top of their lungs that the party must oppose it -- which left options one (an election) or two (the coalition) as the only two acceptable options to the Liberal caucus. It really was at that point a binary choice and given the fact that another election wasn't a real option, the coalition was, in many ways, the default option.
Lots has been written by people (myself included) about whether that calculus was a mistake but those were the options.
I have no idea which of the four options set out above will be on the table after the budget is presented but as Michael Ignatieff has said, how can I possibly speculate on what the Liberal party response will be when I have no idea what will actually be in the budget.
In other words, to answer your question directly, I don't think the Liberal Party's support for the coalition -- if it is there after the budget -- will have much at all to do with an evaluation of how the NDP has evolved under Jack Layton. That's simply not the driver for any Liberal I know towards the coalition.
Needless to say, if there is a coalition, the NDP will try to use it as a seal of approval that they are a responsible party that can be trusted with power -- as they should -- but I'm not sure that's why the coalition was or might be considered by the Liberals.