Ted Cruz is an arch-opportunist and demagogue, so it is telling that he thinks he can gain an advantage by bashing Rubio on foreign policy:

Ted Cruz on Monday offered his strongest denunciation so far of Marco Rubio’s foreign policy views, assailing his Republican presidential rival as a proponent of “military adventurism” that he said has benefited Islamic militant groups. He even tied the Floridian to Democratic front-runner Hillary Clinton.

Cruz is right to fault Rubio for the latter’s support of the Libyan war, and it’s entirely fair to point out that Rubio’s enthusiasm for U.S. intervention in Libya aligns him closely with Clinton on that particular issue. Contrary to what he and his boosters would tell you, Rubio is vulnerable on foreign policy because he is far too eager to favor intervention overseas regardless of the circumstances. That reminds voters that Rubio is in the awkward and politically poisonous position of having endorsed some Obama administration policies overseas that Clinton also supported. It gives Republican voters reason to doubt Rubio’s effectiveness as an opponent of Clinton, and it reminds conservatives that Rubio has repeatedly sided with Obama and Clinton on high-profile issues in the past.

While this attack could hurt Rubio by deservedly poking holes in his exaggerated reputation on foreign policy, it may not do very much for Cruz. Cruz’s own foreign policy record is muddled and difficult to defend. He tries to poach ideas from different factions without identifying himself with any of them. He sounds like the most brainwashed neoconservative when talking about the nuclear deal with Iran, but then suddenly sounds like a cautious realist on Syria. That is what comes of Cruz’s instinct to say whatever he thinks his core supporters want to hear. Cruz doesn’t have a consistent or coherent foreign policy worldview other than doing what he thinks is best for his own political prospects. The problem for Cruz is that his split-the-difference approach to foreign policy disagreements in the GOP has made him appear too hawkish to the non-interventionists and realists and insufficiently aggressive to the hawks. He likes to think that he is occupying a broad middle ground between the party’s two poles, but the reality is that he antagonizes most of the people GOP that care the most about foreign policy. He is saying many of the right things on Syria as far as advocates of foreign policy restraint are concerned, but we also know that he is a shameless demagogue who can’t be trusted.

Despite all that, Cruz makes some fair points against Rubio and the other Syria hawks in both parties:

On Syria, Cruz inveighed against Rubio and Clinton for supporting a no-fly zone and arming “the so-called moderate rebels.” “I think none of that makes any sense. In my view, we have no dog in the fight of the Syrian civil war [bold mine-DL],” he said, arguing that Rubio and Clinton “are repeating the very same mistakes they made in Libya. They’ve demonstrated they’ve learned nothing.”

This is a simple and effective indictment of the Syria hawks’ preferred policies. If it were coming from someone more credible than Cruz, it might do more to generate a serious foreign policy debate among the presidential candidates. Unfortunately, because Cruz is the one saying it, it will be only too easy to dismiss it like so many other things that he says. Any cause that Cruz chooses to use as a vehicle for his own self-promotion is harmed by his support.