Excessive stimulus now being pulled back. Some inflation was (an unstated) part of  policy design, necessary to trigger supply normalisation post lockdowns, but calibration of  size and duration of stimulus was hard. Evidence shows excesses on both fronts: monetary  (as seen in large overnight surpluses) and fiscal (global retail sales were well above trend). 

The pullback is underway, just when price signals trigger the expected supply response  (except in energy), and global retail sales may have already fallen below trend. ~90% of  the fiscal stimulus and 55% of incremental money globally came from advanced economies,  but spillover effects drove up money growth in several EMs too.

Can US inflation show up outside the US too? The risk of inflation persistence is the  highest in the US. It is the only major economy with retail sales much above trend,  investment growth closest to pre-Covid levels, high M2 growth even on a high base, and  the tightest labour market, with wage growth above trend. US inflation should fall from  current levels, but inflation expectations have moved up, not just in markets (50-100 bp)  but also in surveys (~2 pp). In the past, goods inflation has been much more transmissible  but services less so. As improving supply moderates goods inflation, even if wage growth  keeps services inflation elevated, the risk of inflation in Asian economies is much lower.