STORY: U.S. stocks ended narrowly mixed after a volatile session on Monday, with the Dow ticking down marginally, the S&P 500 ending close to flat and the Nasdaq adding just over a third of a percent.Shares dropped early following weekend U.S. and Israeli strikes on Iran.But bargain-hunting investors bought on dips as the day went on, showing an expectation that the disruptions from the conflict will be limited.Defense shares got a boost, with Lockheed Martin and Palantir Technologies gaining more than 3% and 5%, respectively.Joseph Shaposhnik is founder and CEO of Rainwater Equity."I believe the backdrop of this conflict continues to be supportive of our thesis, which is that we're in a defense supercycle. Clearly, European countries will be investing hundreds and hundreds of billions of dollars more over the next ten years to reach their defense targets as a percentage of GDP. Clearly, the US defense budget is going to significantly increase over the next couple of years and certainly this conflict is catalyzing investor interest in defense stocks, which we think have quite long legs over the next couple of years."Among other gainers, energy companies, whose profits rise alongside oil prices, outperformed, with shares of Exxon Mobil and Chevron both closing higher.On the downside, travel and airline stocks sank due to flight cancellations, higher jet fuel costs and widespread Middle East airspace closures.Shares of Carnival tumbled more than 7.5%, while JetBlue lost more than 5.5%, with Delta, American and United Airlines all also closing lower.Other notable stock moves included AES Corp, which plummeted more than 17%, after a consortium led by BlackRock-owned Global Infrastructure Partners and equity firm EQT AB agreed to acquire the utilities company for more than $33 billion.The sharp move lower suggested shareholders were disappointed with the $15-a-share price, which represented a 13% discount to AES' last close on Friday.