Ever since its foundation in 1996, Major League Soccer has faced questions about its place within the world of American sports and global soccer. What is the relationship between MLS and the top football leagues of Europe? Is it a retirement league for aging superstars, a development league for those on their way to bigger things, or a home for the lateral career move, a kind of footballing purgatory? Where should it sit in the American sporting calendar, and what should be the competition’s relationship to the surrounding culture: is MLS an American sporting league whose sport happens to be soccer, or a soccer league that happens to take place in America?

There are questions of direction as well. What is the correct tempo for the competition’s growth, and what kind of league should expansion aim to create? Is this a league that wants to compete with the best of the best, or simply seeks to serve a gap in the domestic market? Aspirationally, is MLS a “world league” in the mold of the Premier League, a league that serves as a center of gravity for playing talent throughout the western hemisphere, or something more modest?

As MLS begins its thirtieth season this weekend, these questions remain as pertinent and tantalizingly open as ever. But this season also promises some measure of clarification, an interim verdict of sorts: in June and July, as the league continues to weigh a schedule change that would bring its season in line with European club football’s fall-to-spring calendar, MLS will pause for the Club World Cup taking place on American soil. This edition of Fifa’s top club competition is, of course, a certified big deal. It will function both as the launch of an expanded 32-team format meant to give a competition once seen as an afterthought some real meaning, and as the curtain raiser for next year’s North American World Cup – a critical juncture in soccer’s ongoing effort to conquer the world’s biggest media market.

As big as this summer will be for Fifa, it will be even bigger for MLS: the participation of Seattle Sounders and Inter Miami in the Club World Cup – the former qualifying via their historic 2022 Concacaf Champions Cup title, the latter via an elaborate, Fifa-stamped approval process known as “getting knocked out in the opening rounds of the MLS playoffs but having Lionel Messi on your team” – will offer a benchmark for MLS’s progress against some of the world’s best clubs. Inter Miami have been handed a relatively friendly group with Palmeiras, Porto, and Al Ahly, while Seattle face a sterner test, with PSG, Atlético Madrid, and Botafogo standing in the way of their progression to the knockout rounds. Since his arrival in Miami one and a half seasons ago, Messi’s MLS appearances have inspired as much admiration for his on-field sorcery as they have derision for the quality of the defending he’s faced; whether fairly or not, popular perceptions of MLS are that of a footballing backwater. The Club World Cup is the league’s big chance to silence the doubters. Do the US’s best clubs – however creatively defined – truly belong on the world stage? Is MLS, as it’s sometimes claimed, the strongest and most competitive league outside Europe’s Big Five? We are about to find out.

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MLS commissioner Don Garber, perhaps wary of how damaging a poor showing from the league’s two representatives could be to MLS’s reputation, is doing his best to keep expectations in check.

“Clearly, MLS teams are at the lower quadrant of transfer market value,” Garber told The Athletic after the Club World Cup draw last month. “And that’s something, over time, that I hope will continue to grow as our teams are investing more in players and hopefully generating more revenue to justify that expense.”

Garber is right, of course. Even in European soccer’s new age of financial controls and profitability rulings, salary cap-constrained MLS teams simply can’t compete with the big clubs across the Atlantic. But his response was also uncharacteristically downbeat. Just a few weeks earlier, he told a sports investment conference that the top European leagues would be in “much, much better shape” if they were more like MLS. That was a much more representative expression of his customary braggadocio, and it also captures some of the tensions and growing pains besetting the league on the eve of its thirtieth season.

By most measures MLS has been a roaring success: average match attendance last season reached a record 23,234, and this year the league will welcome San Diego FC as its 30th franchise. On the field things are humming along nicely enough. Celebrity pre-retirees like Messi and Luis Suárez bring headline pizzazz, but the league has also provided fertile terrain for younger players looking for a mid-career reset (Evander, Denis Bouanga, Riqui Puig). Expansion has brought new investors and fans to the sport, while changing the very fabric of the US’s built environment: soccer-specific stadiums are now a feature of most cities with MLS franchises, giving professional soccer a tangible presence in that it once lacked in the country.

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But in some ways the league has become a victim of this success; the mechanisms that have allowed it to expand so healthily over the past three decades now seem like obstacles to future development. Salary caps have helped keep the league even during the first decades of its growth, and aggressive expansion of the type Garber has pursued makes sense for a country with a population of 330 million and an insatiable appetite for professional sports. Why shouldn’t North America’s top soccer league have 30 teams? On the other hand: should it have 30 teams? And where do you draw the line?

Culturally MLS remains a bit of a non-entity. This is a league that benefits from America’s size, the country’s undiminished capacity to absorb and finance myriad cultures and sporting enthusiasms, while barely making an impression on the national consciousness. Soccer, for all its local advances over the past few decades, still hovers beyond the mainstream. The Messi show might coax LeBron James and Serena Williams out to Chase Stadium on occasion, but the MLS playoffs command none of the attention and prestige of the post-seasons in baseball, football, basketball, or even hockey. MLS seems simultaneously too American for most international football fans (cue jokes about Dick’s Sporting Goods Park and Lower.com Field) and too international for the casual American sports lover; an import that’s been tolerated but never truly embraced. The 18 months ahead, with World Cups at both club and national level to look forward to, will give soccer an unprecedented burst of exposure on these shores. These should be MLS’s golden days. So why don’t they feel like it?

MLS is now at the point where the structures put in place to ensure equitable development of soccer in the US are starting to eat into each other: a salary cap and league expansion may make sense on their own, but a salary cap combined with an ongoing imperative of growth potentially limit the quality of play on the field, which is the most vital commodity of any professional sports competition. Meanwhile the fees to join the league have become so prohibitive – San Diego’s owners paid MLS $500m to become the league’s 30th team – that new franchises risk taking shape in a way that leaves them unconnected to the local communities they’re designed to serve, further undermining one of the rationales for salary caps and other aspects of the league’s institutional design.

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A multi-divisional system built on promotion and relegation could arguably fix most of these problems, allowing for healthy expansion of American professional soccer in a way that accommodates clubs of different sizes and means while maintaining a high standard of on-field quality at the very top of the sport. It would also inject professional soccer in this country with something that other US pro sports leagues lack: a real and dynamic sense of stakes, of permanent divisional jeopardy. Relegation and promotion battles would help MLS further stand out in a crowded domestic sporting landscape, giving soccer a point of differentiation over other sports reliant on the same post-season pop to generate mainstream interest.

But MLS’s design as a single legal entity that owns all the teams – a major point of contrast with the leagues of Europe, where clubs operate as separate legal bodies then own a stake in whichever league they operate in – prevents any kind of opening along these lines. And other aspects of the league’s operational strategy militate against it: potential new team owners, for instance, will probably not want to invest millions into a team if there is a danger of relegation lurking on the horizon. With major structural reform unlikely, MLS could easily expand to 40 teams and beyond (though probably not in short order – Garber said last year that San Diego would be “the end of expansion for a period of time until we’re ready to expand again.”)

Ordinarily one might expect the United States’ cult of competition to encourage rival leagues to emerge in the shadow of this bloat, but challenges to MLS’s domestic supremacy pose little threat, for now at least. A jury recently dismissed an anti-trust action brought by the now defunct North American Soccer League over MLS’s alleged strangling of lower league soccer; meanwhile United Soccer League, a would-be rival to MLS, has announced plans to launch a division one men’s professional league in 2027. But that plan is only in its embryonic stage.

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MLS has the power of incumbency, with all its financial, physical and cultural assets: media and sponsorship deals, stadiums, fanbases. Moves from upstart leagues like USL seem unlikely to prompt much soul searching among Garber and his associates. Displays of short-term progress remain the league’s priority over the more disruptive decisions needed to reform US professional soccer and put the domestic game on a sustainable long-term footing.

Emblematic of this curiously dynamic stasis is MLS’s 2023 decision to ink a ten-year, $2.5bn broadcast deal with Apple. Superficially this deal presents a real marker of progress. In 1999, the year Garber took over as commissioner the status of soccer in this country was so dire that the league eventually formed its own marketing company to produce and distribute the 2002 and 2006 World Cups. But in another sense the Apple deal, which makes all matches available on Apple TV via the $15 per month MLS Season Pass, limits the sport’s potential audience. The league’s reach on cable TV now barely extends beyond the one game a week shown on Fox Sports. Apple TV’s live broadcasts may be high quality but the success of the streaming deal remains hard to gauge, since Apple and MLS refuse to disclose subscriber numbers.

The arrangement boxes in the league in other ways. Apple TV is releasing an “eight-part panoramic documentary event” based on the 2024 MLS season this week – but is there a point in evangelizing to existing subscribers? Drive to Survive did a lot to build Formula One’s popularity in the US but it didn’t do it from behind the same paywall; it was out there on Netflix with all the other slop.

The Apple deal was designed, at least in part, as a sweetener to entice Messi to play out his career in America: Inter Miami’s star attraction receives a cut of the MLS Season Pass subscription windfall as part of his pay package. In no other top professional football league would the administration have the centralized power to decree a deal of this nature; but in no other top league would it be deemed necessary to bet so heavily on a single player.

This is the bind in which MLS finds itself as it enters its thirties: its greatest institutional strengths are also its biggest weaknesses. Efficiency has given way to rigidity, short-term gimmicks take precedence over long-term repairs, and expansion is transforming into stagnation. Garber’s boundless rhetorical confidence in the destiny of the sport in this country seemingly belies some unresolved insecurity. Soccer wants America. But does America want soccer?