• Sweden joins NATO, expanding the alliance as Russia wages war on Ukraine.
• Hospital giant HCA Healthcare suffered a broad data breach.
• The PGA Tour will defend its LIV Golf deal in front of a Senate hearing.

Here are the most important news items that investors need to start their trading day:

1. Waiting game

U.S. stock markets got off to a decent start this week. On Monday, all three major indices finished higher, with the S&P 500 and the Nasdaq squeaking out gains. Investors will be in a bit of a holding pattern Tuesday, as they await fresh inflation data ahead of the Federal Reserve's meeting later this month. Wednesday brings the closely watched consumer price index reading for June, while data about wholesale inflation comes out Thursday. Earnings season kicks off this week, as well. PepsiCo and Delta Air Lines report Thursday, while JPMorgan, Citigroup, Wells Fargo and UnitedHealth go Friday morning. Follow live market updates.

2. NATO set to grow again

The NATO alliance is on the verge of growing even stronger. Turkey on Monday dropped its opposition to Sweden joining the group, paving the way for the Nordic country's membership. Sweden's admission will follow that of Finland, which officially joined earlier this year. NATO's growth is a direct reaction to Russia's invasion of Ukraine. Russian President Vladimir Putin has often criticized the organization as a threat to his country. While NATO leaders meet this week in the former Soviet nation of Lithuania, the fighting continues in Ukraine, with more than 300 Russian airstrikes coming in recent days. Follow live war updates.

3. HCA Healthcare suffers data breach

Hackers stole millions of patients' data from hospital giant HCA Healthcare and posted the information for sale online. The breach affects patients in more than 20 states, including in Florida and Texas. "This may be one of the biggest health care-related breaches of the year and one of the biggest of all time," analyst Brett Callow told CNBC. It doesn't appear the hackers took critical medical records. Still, Callow said the perpetrators claim to have emails with some medical information tied to patients.

4. Apple jumps on WeChat

Apple has its eyes on India's growing economy, but it's also not giving up on the massive Chinese market, either. The tech giant on Tuesday launched an online store on Tencent's WeChat, the largest messaging platform in China. It has 1.2 billion users, who depend on it for communication as well as travel arrangements and bill payments. China remains a powerful market for Apple. Even as smartphone sales sagged on an annual basis during the first quarter in the country, iPhone sales increased 6% year-over-year, according to Counterpoint Research.

5. PGA Tour defends LIV Golf deal

The PGA Tour will make the case for its deal with Saudi-backed LIV Golf on Tuesday at a Senate hearing. The tour's operating chief, Ron Price, is set to argue that the deal, which would combine the organizations' businesses into a new subsidiary, shouldn't be considered a merger. Meanwhile, Saudi Arabia's Public Investment Fund will be a minority investor with no controlling interest, according to Price. The PGA Tour announced the merger with scant details early in June. Nonetheless, it triggered a wave of outrage among golfers, fans and lawmakers, who slammed the kingdom's record of human rights violations and its links to the murder of journalist Jamal Khashoggi and the 9/11 terrorist attacks.

– CNBC's Sarah Min, Natasha Turak, Lee Ying Shan, Rohan Goswami, Arjun Kharpal and Lillian Rizzo contributed to this report.

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