Increasing geopolitical tensions sent U.S. investors out of stocks and into safe havens such as Treasuries and the dollar on Tuesday, after the U.S. warned it had indications that Iran may be planning a ballistic missile strike against Israel.

The S&P 500 was recently down 1.1% while the Nasdaq Composite Index was off 1.6%. The dollar was up 0.4% against a basket of currencies. The U.S. benchmark 10-year Treasury yield was recently down about 8 basis points at 3.72%.

QUOTES FROM TRADERS IN THE US AND AROUND THE WORLD:

ALLAN SMALL, SENIOR INVESTMENT ADVISOR, ALLAN SMALL FINANCIAL GROUP WITH IA PRIVATE WEALTH, TORONTO

"Markets had gotten used to a lot of geopolitics as Israel continued its fight in Gaza and with Hamas; it seemed like that wasn't affecting markets much. It seemed like a lot of the fighting had been done already and that was winding down and then here we are - a new spark comes up. The market will sell off on that headline, whether or not it rebounds today or tomorrow depends on whether the headline coming out now is valid or not.

"If the war escalates, that of course is not good for markets but would be good for the price of oil, gold and those stocks though most of the other stocks would probably sell off like we're seeing today."

MICHAEL BROWN, SENIOR RESEARCH STRATEGIST, PEPPERSTONE, LONDON

"I think the initial market reaction to the news has been pretty much exactly as one would have expected, with a knee-jerk risk-off vibe sweeping across the board, as the dollar vaulted to day-highs, along with gold and long-end Treasuries, while stocks and higher beta G10s slumped."

"The key question now is the degree to which these initial moves are consolidated, or pare back, which hinges almost entirely on whether an Iranian attack is indeed forthcoming. Markets, hence, are likely to display an incredibly high sensitivity to incoming geopolitical news flow in the coming hours. Though, if recent reports are to be believed and the aforementioned attack is similar in scale to that delivered in April, this could be greeted with a sigh of relief, and not be interpreted as a significant sign of escalation beyond what has already been seen."

ANTHONY SAGLIMBENE, CHIEF MARKET STRATEGIST, AMERIPRISE FINANCIAL, TROY, MICHIGAN

"The situation in the Middle East continues to evolve rapidly. With Iran and Lebanon being drawn into the Middle East conflict more directly, reactions today are playing out in higher crude and gold prices. While rising geopolitical tensions create elevated market uncertainty and anxiety over the near term, investors will likely measure the longer-term impact of growing Middle East conflict through potential impacts on oil supply."

WALTER TODD, CHIEF INVESTMENT OFFICER, GREENWOOD CAPITAL, GREENWOOD, SOUTH CAROLINA

"It's obviously risk-off. People will buy up Treasuries, sell stocks, buy oil - all the normal things you would think of in this situation."

"This highlights the circumstance of this market in the fact that there are a myriad of risks out there, whether that's slowing employment in the U.S., the geopolitical tensions in Ukraine, the Middle East. And the market seems very mispriced for any flare-up of any of those risks... It's vulnerable to shocks like this."

LOU BASENESE, PRESIDENT AND CHIEF MARKET STRATEGIST, MDB CAPITAL, NEW YORK

"The markets are acting predictably. In the lead-up to and outbreak of war or geopolitical crises, major indexes sell off reflexively, dropping an average of 5% to 7%. The selling pressure typically lasts for about two weeks. Within another two weeks, though, they typically recover. So trading around the fear or outbreak is a risky proposition at best.

"That said, the nature of each conflict can have more lasting impacts on individual sectors or areas of the market, like oil and defense stocks. In this case, we'd be hard pressed to find anyone that disagrees that an Iranian attack would be a major escalation and indication of a protracted conflict, which should keep driving both oil and defense stocks higher."