It bears repeating that the situation is fluid, the truce is fragile, and nerves are stretched, reflected by Trump's expletive-laced rebuke of both countries early on Tuesday before he departed for a NATO summit in the Netherlands.
But the market mood is buoyant. Just look at the oil price - its reversal in the first two trading days of the week has been extraordinary, with Brent crude futures recording a peak-to-trough decline of 18%.
Oil is a smaller input in global industry, economic activity, and inflation today compared with decades gone by, but it is still significant. Oil is now 20% lower than it was this time last year, which is good news for consumers, businesses and, from an inflation standpoint, central banks.
Fed Chair Jerome Powell's semi-annual testimony to Congress was the other main area of focus for investors on Tuesday, and they will have been relieved there was no hawkish curveball on the rate outlook.
Powell repeated his position from last week's post-meeting press conference that policymakers can afford to wait and see the impact of tariffs on activity and prices before deciding their next step.
"I do not want to point to a particular meeting. I don't think we need to be in any rush," he told lawmakers, distancing himself from some of his colleagues who have said recently they would consider cutting rates next month.
But Powell wasn't any more hawkish than he was last week, and his steady steer helped pave the way for the rally.
Despite the optimism washing over markets this week, there are reasons to be cautious on the U.S. economy. Figures on Tuesday showed that consumer confidence is falling, with pessimism toward the jobs market at its lowest level in over four years, and the current account deficit widened to a record $450 billion in the first quarter.