Learn Hardcore German: Die Zeitung betonte, dass globale Netzwerke den Einfluss einzelner Städte stärken können. - The newspaper emphasized that global networks can strengthen the influence of individual cities.

Because the clause is introduced by the subordinating conjunction dass, German grammar requires the finite verb to go to the very end. Here können is the finite (conjugated) modal verb in the third-person plural, so it must come last. The main verb stärken remains in the infinitive and therefore directly precedes the modal, giving …dass … stärken können.

What case is einzelner Städte, and why is it used here?

einzelner Städte is genitive plural. It modifies the noun Einfluss (which is masculine), so “the influence of individual cities” becomes der Einfluss einzelner Städte. In genitive plural, adjectives take the strong ending -er and the noun stays in its plural form.

Why is there no article before globale Netzwerke?

Because the sentence speaks about global networks in general. In German, when you refer to something in a broad or indefinite sense (especially in plural), you often omit the article: globale Netzwerke = global networks (as a general concept). If you wanted to specify certain networks, you could say die globalen Netzwerke.

Why is dass spelled with double s, and how can I tell it apart from das?

dass with ss is the conjunction meaning that, used to introduce subordinate clauses. das with a single s is either the neuter definite article or a relative/pronoun. A handy trick: if you can replace the word with welches (which) or dieses (this), it’s the pronoun/article das; if it introduces a clause, it’s the conjunction dass.

Why is betonte in the simple past (Präteritum) instead of the perfect tense?

In written German—especially in journalism, reports and formal writing—the simple past (Präteritum) is preferred for verbs like betonen. In everyday spoken German you’d more often hear the perfect: hat betont, but in a newspaper style Die Zeitung betonte sounds more natural.

Could I use the subjunctive and write könnten instead of können?

Yes. If you want to signal reported speech or add an extra distance/uncertainty, you could use Konjunktiv II:
Die Zeitung betonte, dass globale Netzwerke den Einfluss einzelner Städte stärken könnten.
Here the indicative können treats the possibility as more factual, while könnten flags it as a potential or indirectly reported claim.

Can I place the dass-clause at the very beginning of the sentence?

Absolutely. German allows fronting of subordinate clauses. You’d then write:
Dass globale Netzwerke den Einfluss einzelner Städte stärken können, betonte die Zeitung.
Notice that after a fronted clause the conjugated verb betonte still occupies the second position in the main clause.

Is hervorheben interchangeable with betonen here?

They’re very similar: betonen means to emphasize or stress, while hervorheben means to highlight or bring out. You could say
Die Zeitung hob hervor, dass …,
but it carries a slightly more formal or stylistic tone. Both convey the idea of drawing attention to something.