As Federal Reserve officials pursue the most aggressive monetary policy stimulus campaign in their institution’s history, they are mindful of the unintended consequences their actions can have on financial markets.

But as it now stands, most remain confident that huge injections of money into the economy haven’t created any bubbles big enough to threaten the overall course of the recovery. That has allowed them to press forward with their aggressive agenda of bond buying, which is aimed at pushing up asset prices in a bid to boost growth and lower unemployment.