They didn’t spend during the bust. They spent to elongate the boom. Subtle but important difference.
At what point does national debt become unsustainable? If you spend in the boom and don’t save (as happened) how can you spend anything when you don’t have anything. Credit rating is important, it would have been close to bankrupting the country.
The overwhelming share of the spending spike in 2008 and 2009 came from having to prevent the entire financial system melting down (exacerbated by a decade-long bipartisan push for mindless financialisation and deregulation) - so, hardly 'unsolicited' spending, unless you're a full-on Mad Max libertarian.
And anyhow, even if (for the sake of argument - I'm not conceding the point) Labour spending was excessive before the crash, it doesn't change that austerity during the recession is every bit as procyclical as spending during a boom, to far more disastrous effect.
What is even worse is that due to austerity in the EU and especially the UK, monetary policy has had to do all the lifting, such that we now have trillions of conjured QE money sloshing around with no productive place to go, distorting markets through cheap money-driven M&A consolidation, and asset bubbles in real estate and equities. This in turn has made housing unaffordable for an entire generation, suppressed wages even at allegedly full employment, stalled productivity growth (why risk spending on research and innovation why you can use the tidal wave of essentially interest-free QE money to just buy back your own shares instead), deligitimised liberal democracy across the West, and fueled inequality not seen since the Victorians (of course, equities and real estate are mostly excluded from inflation calculations, and as policy makers have discovered, you can invent trillions of dollars and even risk deflation!!! so long as you strike real estate/equities from the ledger and ensure that no ordinary people get so much as a whiff of the effectively invented bailout money).
We are now entering a world where negative interest rates are increasingly the norm, perhaps soon even in America, yet even now, with pension funds and the bond markets on their knees begging, governments still refuse to invest (even as our schools can no longer afford to stay open for the full week). The entire developed world could end up like 90s Japan. Take Germany, which is dutifully racking up pointless surpluses while its roads fall apart, its telecom infrastructure has become the laughingstock of Western Europe, inequality skyrockets, and its industrial champions - the sole basis of its postwar prosperity - have their lunch eaten by competitors in countries like China which have ignored the IMF and Milton Friedman to world-historical effect, and which are investing in productive and future world-leading outputs like 5G or renewable fuel cells, rather than in new ways to cheat on emissions tests.
We have by now essentially broken the global bond market - which is to say, pension funds, and have spent the past ten years creating dozens of overlapping speculative bubbles, as even investors who represent actual workers and who want nothing more than safe long term growth are forced to pump money into high risk private equity and fake tech nonsense like Wework and Uber, if not Theranos, just to eke out returns.
Even the unemployment figures you refer to are in practice mostly nonsense, because the jobs are all terrible zero-hours gig economy stop gaps that don't pay people enough to pay the rent or support a family.
And the worst thing is that when the overlapping speculative bubbles pumped up by the avalanche of QE money inevitably burst, there will be virtually no monetary recourse, because the economy will have collapsed with the central banks' hands already pulling full throttle on the emergency lever.
We could have avoided all of this with basic Keynesian countercyclical fiscal policy, but instead, we fall back on the disease of an idea that governments which borrow in currency upon whose creation they enjoy a monopoly!!! should comport themselves like bourgeois fantasies of how a working class household is supposed to behave.
Now, tell me why I'm all wrong and all of this is actually brilliant.
I am genuinely curious (but also bracing myself) to hear what they are teaching these days in Econ school.
