US stocks slipped at the opening of the second half of the year, with a cautious start to July and the third quarter as renewed tensions surrounding the United States and Iran weighed on sentiment and technology shares pulled back. The subdued open followed a first half in which equities had powered to a record-setting quarter, and it underscored how quickly the mood can shift after a strong run.

Wall Street opened lower as the geopolitical backdrop clouded the start of the new period. Lingering uncertainty over the situation between the US and Iran unsettled investors, offsetting the momentum that had carried markets to their best quarterly performance in years. The pullback suggested that, after such a powerful advance, traders were inclined toward caution rather than chasing the rally further into the new quarter.

Technology shares, which had led the market's charge through the first half, were among those retreating as the quarter turned. The sector had been the engine of the first-half rally, driven by enthusiasm for the artificial-intelligence build-out, and its softness at the open reflected some profit-taking and a reassessment of stretched valuations after an extended climb. A retreat in the biggest winners can weigh heavily on the broad indexes given their outsized influence.

Across the Atlantic, European markets echoed the cautious tone, with equities easing and oil prices holding lower as the new month began. The parallel softness pointed to a broadly risk-off session rather than a purely US phenomenon, as investors globally digested the shift from a buoyant first half into a period thick with event risk, including central bank commentary and a key US jobs report later in the week.

The retreat in oil added another layer to the picture. Crude prices stayed under pressure as progress in talks between the US and Iran eased fears of supply disrunet, and softer energy prices rippled through related equity sectors. The combination of geopolitical caution and falling oil left markets without a clear directional catalyst at the open, contributing to the tentative tone.

The session also unfolded against a busy macro calendar. Investors were weighing fresh data on the US economy, including a softer-than-expected reading on private hiring and a manufacturing gauge that came in below forecasts, alongside anticipation of commentary from Federal Reserve officials. That mix of incoming information gave traders reason to tread carefully, particularly with a pivotal employment report looming that could reshape expectations for interest rates.

Whether the soft start marks a brief pause or the beginning of a broader consolidation remains to be seen. After a first half defined by a relentless, AI-led advance, the market enters the second half facing a fuller slate of risks, from geopolitics to monetary policy to stretched valuations in the leadership names. The tentative open served as a reminder that the conditions that fueled the first-half rally may face sterner tests in the months ahead, with the coming data and policy signals likely to set the tone.