-Obama in Cuba and Argentina. The president’s historic visit to Cuba, begun on Sunday, will rightly get more attention than his stop in Argentina afterward. But it may be instructive to watch closely the tone of his speeches, activities, and interactions with the leaders of each nation, as signals of how America regards them. What a contrast. Cuban President Raul Castro has shown no inclination to reform his failing economy, which produces per capita GDP that’s a small fraction of most of his Caribbean neighbors’, or to loosen his brutal dictatorship, which receives the lowest possible rating in the latest freedom ranking by Freedom in the World.

Argentina’s new president, Mauricio Macri, is taking the helm of another pathetic economy but steering in a radically different direction, courting business, removing currency controls, accepting a drastic devaluation of the currency as a necessary start to recovery, and taking first steps toward freer trade; he’s also chilling the country’s formerly friendly relations with Venezuela and Iran.

When Obama’s trip is over, what will the world conclude about his feelings toward each leader?

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-Tim Cook’s strategy for Apple’s future. He will introduce new products on Monday, and while they’ll undoubtedly be cool and maybe even surprising, the real issue for the company is whether they’ll noticeably move the needle on revenue and profit. Apple (AAPL) is still the world’s most valuable publicly traded company, and value is based entirely on expectations of future growth. Some analysts believe Apple’s 2016 revenue may be less than last year’s, the first such decline in over a decade. Will Cook show them anything that changes their expectations? And if not, will Apple’s valuation trend downward long-term?

-Mitch McConnell’s leadership of the Merrick Garland Supreme Court battle. The Senate majority leader was definitive on the Sunday morning talk shows: This Senate will not consider President Obama’s Supreme Court nominee at any time, period. Other GOP senators, including powerful ones, are breaking ranks. Orrin Hatch of Utah last week said that if Hillary Clinton or Bernie Sanders were to win the election, he’d be open to considering Garland in the lame duck session. Mark Kirk of Illinois went further, saying flatly that his fellow Republicans should “just man up and cast a vote.”

The Senate has now gone home for a two-week recess. If senators hear from constituents that they think McConnell is wrong—a substantial possibility, according to polling—will they try to change his mind? Will some oppose him publicly? And what will he do if, as summer turns to fall, his position seems to be damaging the Republican presidential nominee, whoever he may be?

-Trump vs. Cruz in Arizona and Utah. The numbers of delegates aren’t big, but at this point each one counts. The big question will be whether the anyone-but-Trump movement—and in these two states, Cruz is the only realistic alternative—is gaining steam. Polls predict Trump wins Arizona, Cruz wins Utah.