Mr Bos in an interview with the weekly Elsevier on Tuesday (4 July) indicated that The Hague's opposition to the EU constitution will not weaken under his leadership, following the rejection of the charter by Dutch voters last year.
The prime ministerial hopeful indicated that any revised version of the constitution would be put to Dutch voters again.
"If anything emerges again which is only slightly similar to what was called the Constitutional Treaty last year, this has to be dealt with again through a referendum," Mr Bos said.
Mr Bos added that many of his fellow European social democrat parties "had the illusion that if the PvdA [Dutch Labour] entered government, the constitution would be easily fixed."
These parties are now "extremely nervous" because the Dutch social democrats will not back the EU constitution a second time, he said referring to Labour campaigning on the "yes" side ahead of last year's referendum.
Color me flabbergasted.
He had more to say on the current heading of the EU. It's worth a read.